The control of reproductive cycles in higher primates is largely dependent on negative and positive feedback mechanisms by both steroidal and non-steroidal substances of the ovaries which regulate the function of hypothalamo-pituitary system. To gain insights into the role of INH A, the non steroidal ovarian hormone in the feedback control of pituitary FSH secretion, studies were conducted to examine the interrelationships of hormones throughout the menstrual cycle of the bonnet macaque. The findings of chapter II provide a detailed description of endocrine hormone profile during the menstrual cycle of the bonnet macaques with special attention to the feedback role of INH A on pituitary FSH secretion. To characterize the endocrine profile of different hormones, both ovarian (E2, P4, INH A) and pituitary (FSH, LH) hormones were measured daily for more than 40 days. To further examine the site of secretion of INH A and its relationship with pituitary FSH dynamics, surgical lutectomy and pharmacological induction of luteolysis employing the third generation GnRH R antagonist, Cetrorelix (CET) studies were carried out in the subsequent experiments. The results obtained from these studies suggest that INH A and P4 secreted from the CL during luteal phase regulate pituitary FSH secretion. The selective rise in FSH observed during the late menstrual cycle and during menstruation (referred to as luteo-follicular transition), as has been reported previously in higher primates, considered necessary for initiation of follicular growth and recruitment of follicles for ensuing menstrual cycle was characterized in the monkey. Surgical lutectomy and induction of luteolysis by CET experiments suggested that increased GnRH secretion is essential for this selective rise in FSH following withdrawal of inhibition by P4 and INH A. In clinical cases of reproductive ageing, the shortened follicular phase in human females has been identified to be the result of occurrence of early onset of FSH rise during the luteal-follicular transition period. The cause(s) of declining fertility with age in women who still have regular menstrual cycles are not clear, but issues of relationship between dysregulation of selective FSH rise in the late luteal phase and associated infertility could be examined using bonnet monkey as a model system. INH A is secreted in significant quantities by CL in higher primates and the feto placental unit suggesting its importance during fertility and pregnancy. Apart from the negative feedback regulation of pituitary FSH secretion, the complete repertoire of actions of this hormone during pregnancy is yet to be fully understood. The data presented in this thesis is the first comprehensive report showing the endocrine hormone profile of gonadotropins and ovarian hormones including INH A throughout the menstrual cycle of the bonnet macaque. The characterization of INH A profile in bonnet monkey will be of significant value for studies examining the role of INH A in higher primates. Dimeric inhibin has been suggested to be important for regulation of fertility and reproductive functions. Also, inhibin-α (one of the subunits of the dimeric protein) knock out mice model has provided convincing evidence that it acts as a tumour suppressor. A great deal of new information has been generated in recent years regarding the potential clinical usefulness of monitoring inhibin levels in blood and biological fluids in gynaecological diseases, pathological pregnancies and other disorders. Emerging clinical roles of inhibin have made INH A an important candidate molecule to study its molecular regulation. The results presented in chapter II suggested that LH regulates luteal INH A secretion (induction of luteolysis by CET administration experiment). As a first step towards understanding molecular regulation of inhibin-α expression in the macaque CL, in silico promoter analysis of macaque inhibin-α was performed and it revealed several transcriptional factor binding sites that were conserved across species. In rats FSH up regulates while preovulatory LH surge suppresses inhibin-α mRNA expression in the ovary and this suppression has been suggested to be necessary for occurrence of secondary FSH surge during metestrus. To address differential regulation of inhibin-α by LH and FSH in rat ovary during the periovulatory period, studies employing immature rats were carried out and the results are presented in chapter III. The results suggest that immature rat ovaries respond to exogenous gonadotropins in terms of LH signaling (cAMP production), luteinization (P4 production) and as well induction of ICER expression required for repression of inhibin-α subunit expression. PDE4 inhibitor (rolipram) treatment enhanced the ovarian cAMP concentrations suggesting that PDE4 play a major role in controlling intraovarian cAMP concentrations in rat ovaries. However increased cAMP concentrations did not appear to up regulate the ICER expression at the time point examined in this study. In higher primates time course of second FSH surge and continued synthesis and secretion of INH A in the CL are different from non primate species. In the monkey, the second FSH rise occurs during the late luteal phase and experiments have been carried out to examine the regulation of inhibin-α subunit expression by ICER. Expressions of ICER (mRNA/protein) and INH A were examined during different stages of CL and the results indicated no clear inverse relationship between the ICER and inhibin-α mRNAs. With no conclusive role for the ICER in regulating luteal inhibin-α observed in the study, the role of transcriptional activators in the regulation of inhibin-α like GATA4, SF-1, β-catenin were further examined. Since luteal INH A secretion was dependent on pituitary LH as determined earlier in chapter II, expressions of transcriptional activators were examined in CL of different stages and also during induced luteolysis and the results are described in chapter IV. In conclusion, our results indicate cross talk between WNT, cAMP and P38 MAP kinase signaling pathways in the regulation of luteal INH A secretion. The pituitary gonadotropin, LH, is the primary luteotropin in primate species acting to maintain the structure and function of the CL during the menstrual cycle. However whether the actions of LH are direct or mediated by local factors such as P4 remain unknown. Moreover, P4 secretion which is dominant during luteal phase has any role in regulating CL structure and function is not clearly defined. To address these and issues concerning P4 actions, initially, experiments were performed in the rat model to study the importance of P4 in the regulation of ovarian functions. An antiprogestin, RU486, was employed as a tool to uncover the PR regulated pathways during ovulation in rats and the findings are presented in the chapter V. The results indicated that blockade of PR action by RU486 during gonadotropin-induced superovulation resulted in inhibition of follicular rupture and ovulation in immature rats. Further to understand the downstream effectors of PR action, and to identify the candidate target genes of PR activation, semi-quantitative RT-PCR and western blot analyses were performed. The results obtained indicated that betacellulin, a member of EGF family and MMP-9 a proteolytic enzyme, were markedly repressed in response to RU486 treatment in rat ovaries. Also, the down stream pathway of EGF signaling leading to activation of ERK was markedly repressed in RU486 treated ovaries. It was next examined what role the P4/PR system has in the regulation of CL structure and function. Surprisingly, PR expression is absent in CL of rats, while it is present in higher primates. Experiments were carried out to examine intracrine actions of P4 in the regulation of CL structure and function in monkeys. The recently reported model system of induced luteolysis yet capable of responsive to trophic support from the laboratory provided an ideal opportunity to examine direct effects of P4 on structure and function of CL in the monkey. A series of pilot experiments were carried out in monkeys experiencing summer amenorrhea, to determine dose and mode of administration of exogeneous P4 to simulate mid luteal phase circulating P4 concentrations in monkeys subjected to induced luteolysis. Based on the results of pilot experiments, implantation of Alzet pumps containing 97.5mg of P4 was selected for maintaining mid luteal phase P4 concentrations. The microarray data of induced luteolysis previously deposited by the laboratory in NGBI’s gene expression omnibus were mined for identification and validation of differentially expressed genes of PR and its target genes following LH depletion and LH replacement experiments. Expressions of PR, PR cofactors and expressions of PR downstream target genes through out the luteal phase and in CL from day1 of menses were also examined. Analysis of expressions of genes revealed that of the 45 genes identified to be regulated by LH treatment, 4 genes were found to be responsive to P4, and 14 were identified to be responsive to both P4 and LH. Morphology of CL tissue sections revealed that P4 treatment appeared to have reversed the induced-luteolysis changes. In another experiment, implantation of P4 during late luteal phase (i.e., the period of declining P4 concentrations) for 24h caused changes in expressions of genes associated with tissue remodeling and morphology of luteal cells. Taken together, the results suggest that induced luteolysis plus P4 replacement model is suitable for assessing the effects of P4 on CL function. The results also suggest that CL could serve as target tissue for examining the genomic and non genomic actions of P4. In summary, studies carried out in the present thesis provides a comprehensive endocrine hormone profile throughout the menstrual cycle of the bonnet monkey with special emphasis on time course of INH A and FSH secretion which is very useful for future investigations. Studies have been carried out in rats and monkeys with different experimental model systems to address molecular mechanisms underlying inhibin-α regulation in the ovary in general and CL in particular. Experimental findings in monkeys could help elucidate the underlying molecular nature of CL functionality and extrapolate to understand luteal insufficiency and infertility producing conditions in humans. Also different model systems have been validated to examine the actions of P4/PR system in rats and monkeys and more importantly to address the direct effects of P4 upon monkey CL structure and function were established. Future investigations based on findings of these studies should help clarify relative roles for LH and P4 during maintenance of CL function and luteolysis.

Corpus luteum is a transient endocrine structure formed from the ruptured ovarian follicle. Its main function is to secrete P4, a pro-gestational hormone, essential for establishment and maintenance of pregnancy in mammals. The modulators of CL structure and function are classified as trophic and lytic factors. The luteotrophic factors include pituitary hormones, growth factors, intra luteal factors and cytokines, while luteolytic factors include PGF2α and oxytocin. The interplay between luteotrophic and luteolytic factors regulates luteal steroidogenesis. The precise timing of expression of various enzymes/proteins required for synthesis and metabolism of P4 constitutes an important process in the overall regulation of CL function. The three hormones LH/CG, E2 and PRL are regarded as luteotrophic factors crucial for control of CL function in mammals. Depending on species, either individually or all three hormones in the form of luteotrophic complex have been shown to participate in the regulation of CL function. In addition to the well-established endocrine role of E2, its secretion is the hallmark of the ovulating follicle, has an important role in the intraovarian growth, differentiation and survival of cells. Chapter I provides a comprehensive review of literature on CL structure and function with emphasis on factors that influence its growth, development, function and demise in bovines and rodents. In Chapter II, studies have been carried out to examine 20α-HSD expression and its activity in the CL of buffalo cow. During induced and spontaneous luteolysis, rapid fall in circulating P4 is one of the early signs of initiation of luteolytic process in several species. In rodents, it is well recognized that during luteolysis, P4 is catabolized into inactive metabolite, 20α-OHP by the reaction of 20α-HSD enzyme during luteolysis. Experiments were carried out to determine 20α-HSD expression and activity throughout the luteal phase and during induced luteolysis in the buffalo cow. Circulating P4 concentration declined rapidly in response to PGF2α treatment, but HPLC analysis of serum samples did not reveal changes in circulating 20α-OHP levels in buffalo cows. In contrast, pseudo pregnant rats receiving PGF2α treatment showed higher 20α-OHP levels at 24 h post treatment. qPCR expression of 20α-HSD in CL during different stages of luteal phase and PGF2α-treated buffalo cows was carried out and higher expression of 20α-HSD was observed at 3 and 18 h post treatment, but its activity was not altered post PGF2α treatment at other time points examined. The expression of the transcription factor Nurr77 which is involved in increased expression of 20α-HSD increased several fold 3 h post PGF2α treatment similar to the observation in PGF2α-treated pseudo pregnant rats. The results suggested that the synthesis rather than catabolism of P4 appears to be primarily affected by PGF2α treatment in buffalo cows in contrast to increased metabolism of P4 as seen in rodents. In bovines, to date no luteotropic actions for E2 has been demonstrated and whether E2 has direct effect on CL function has also not been reported. Expression of CYP19A1 gene that encodes aromatase enzyme although gets down regulated post ovulation but its expression recovers in the CL and also E2 biosynthesis has been reported in the bovine CL. Recently it was observed that CYP19A1 expression was consistently down regulated following administration of luteolytic dose of PGF2α. Experiments were conducted to examine the expression of ERα and ERβ in the CL throughout the buffalo estrous cycle as well as examined the luteal E2 levels post PGF2α treatment. The results indicated that ER expression was detectable during different stages of CL and that circulating and luteal E2 levels declined post PGF2α treatment. It was hypothesized that decrease in luteal E2 levels leads to down regulation of ER signaling and changes in expression of E2 responsive genes in the CL. To test the hypothesis, 89 genes which were regarded as E2 responsive genes were selected and the previously published global gene expression data of the buffalo CL was mined for E2 responsive genes. It was observed that 57 of 89 genes regarded as E2 responsive genes were found to be differentially expressed. Since non pregnant buffalo CL is not regarded as major site of E2 production, to validate the authenticity of differentially E2 expressed genes post PGF2α, CL of another species, the macaque, which is known to secrete abundant E2 was included for the analysis. Incidentally, the global gene expression data for the PGF2 α treated macaques (in which CYP19A1 gene expression also gets down regulated) has previously been reported from the laboratory. Here again, it was observed that nearly 79 of 89 genes were identified to be differentially expressed. To further determine the consequences of decreased ER signaling, molecules associated with survival and apoptosis were examined. The results indicated decreased expression (both mRNA and protein levels) of Akt, Bax and Bcl-2 genes. The results suggested an important role for E2 on CL function in the buffalo cow. In Chapter III, several experiments were conducted in another model system, pregnant rat, in which aromatase expression and therefore E2 production is high in the CL. Experiments were conducted to examine the effects of E2 inhibition and E2 replacement on the expression of genes. For this purpose, pregnant rats were treated with a specific aromatase inhibitor on day 12-15 of pregnancy. Together with AI, exogenous E2 was administered to another group of pregnant rats. The CL collected from different groups of rats on day 16 of pregnancy was subjected to microarray analysis. The analysis post validation of microarray data has shown that clusters of genes could be segregated into various pathways involving luteal steroidogenesis, immune system, various growth factors and apoptotic processes, all directed towards the regulation of CL function. The involvement of E2 in luteal cell proliferation and lipid deposition well corroborated with protein levels for cyclin D1 and ki67 and the results of oil red O staining, respectively. There have been reports implicating PI3K/Akt signaling in cyclin D1 accumulation, but mechanism of action does not appear to involve transcriptional activation of cyclin D1. The results of the present study indicate a decrease in cyclin D1 protein levels due to inhibition of PI3K/Akt signaling by AI treatment which is prevented upon administration of E2 during AI treatment. The findings provide a comprehensive overview for the mechanisms associated with the cell survival, progression, etc. The bioinformatics approach provided complete landscape of functional changes affected by the upstream regulators of genes associated with survival and apoptosis. Also, the findings further strengthen the hypothesis of involvement of E2 in the regulation of CL function by way of activation of Akt, the primary mediator of PI3K signaling in the regulation of cellular component that affect cell survival. In the present study, IGFBP5 which was up regulated during luteal inhibition of E2 with AI treatment was selected for further studies. Although IGFBP5 is known to be associated with follicular atresia in the rat ovary, there is limited data for the involvement of IGFBP5 in either a growth stimulatory or inhibitory action on ovarian cells. Based on present findings, a causal link between reduced ERα transcriptional activities resulting in inhibition of Akt/PKB in the presence of IGFBP5 expression could be proposed. Further, the cellular hypertrophy mediated by E2 has been speculated due to increased proliferation of vascular endothelial cells, blood supply and thus nutrients. E2, together with PRL and placental lactogens, regulates steroidogenesis and cell hypertrophy in the rat CL of pregnancy. In CL, the prominent IGFBP5 mRNA expression in different types of luteal cells has not been reported. The mRNA expression for IGFBP5 across the two types of luteal cells showed higher expression in SLC. Hence, in the present study, it has been speculated that prevention of conversion of SLC to LLC due to lack of E2 biosynthesis in presence of AI might be acting as a source for the increased IGFBP5 levels during mid pregnancy in rat CL and brings about changes associated with lack of E2. Various receptor studies on rat CL have demonstrated the lack of progesterone receptor (PR) mRNA expression in the rat CL negating its involvement as an autocrine/paracrine regulator of CL function through an intracellular receptor, but the involvement of non-PR involvement in mediating such mechanism further strengthens the role of ERs. The luteotrophic complex formation in pregnant rat principally by PRL and E2 has been discussed at length in Chapter III. PRL appears to maintain luteal ER content in the CL during rat pregnancy which further determines the luteotrophic and luteolytic actions of E2. Further, study on expression of E2 responsive genes would help in identifying E2 regulating molecules to get a clear picture on the role of E2 in understanding regulation of the CL function. The interaction of E2 with growth factor signaling including the IGF pathway has been well established in different species and this interaction is tightly linked to ERα expression, an observation interpreted as physiological coupling of growth factor and stress signaling pathways. Attempts were made towards understanding cross talk between the E2 signaling and the IGF1 signaling in few experiments carried out in Chapter IV. Based on the results, it can be proposed that a causal link exists between reduced ERα transcriptional activity and inhibition of Akt/PKB in the presence of IGFBP5. The present study has shown the activity of IGF on ERα activity mediated partly via PI3K/Akt pathway. Hence, the finding further speculates that inhibitory effect of IGFBP5 on E2 induced ERα function was due to sequestration of IGF1, possibly present in serum or produced within the cells. Another striking observation was the down regulation of glucocorticoid receptor (GR) gene, NR3C1, in the data of earlier studies [Priyanka, 2009, GEO accession number GSE8371 and Kunal, 2014, GEO accession number GSE27961] and the present study has been compared and discussed in this thesis. Glucocorticoids provide key signals for differentiation of fetal and placental tissues. Therefore, regulation of glucocorticoid access to the placenta and fetus is recognized as an important determinant of prognosis outcome and subsequent development of the postnatal phenotype. Differential regulation of these genes in CL post E2 deprivation and replacement further emphasize the regulation of CL via various biological, cellular and molecular functions. Interestingly, besides transcriptional regulation of IGF axis components, E2 activated ERα also rapidly influence the activity of IGF axis related to signaling proteins in a non-genomic manner, especially by the PI3K/Akt pathway. PI3K/Akt pathway analysis has been carried out in E2 inhibition and replacement experiments. To further confirm the observations of E2 and growth factor interaction, experiments have been set up with exogenous GH for increasing circulating levels of IGF in the system. The findings suggest that the non-genomic signaling pathway activated by the phosphorylation of ERα induced by E2 gets inhibited in the presence of AI result in increased expression of IGFBP5. The reduction in circulating IGF1 in pregnant rats may be associated with the effect on IGFBP, important for determining biological action of IGF1. The changes observed in the present study emphasize the exclusive effects of the IGFBP5 on the CL function brought about perturbations in luteal E2 content. The experiments described in the present thesis aim at understanding the mechanism responsible for decreased serum and luteal P4 post PGF2α treatment in buffalo cows, i.e. whether PGF2α acts on biosynthetic or catabolic process of P4. In the present study, experiments were designed to elucidate the role of E2 in regulation of CL function, since down regulation of CYP19A1 gene mRNA was one of the early events observed in buffalo cows post PGF2α treatment. This line of research work was extended to rodents, a species that secretes high levels of E2 during pregnancy. Genome wide transcriptional changes data revealed differential expression of several E2 responsive genes following E2 inhibition and replacement treatments. The results revealed importance of ER-mediated PI3K/Akt signaling essential for regulation of many transcriptional regulatory molecules in the CL and an interesting involvement of IGFBP5 as a link between E2 and IGF signaling. These findings further provide an insight into the role of IGFBP5 in E2-mediated actions in rat CL during pregnancy. In conclusion, the present findings suggest inhibitory effect of IGFBP5 on E2-induced ERα function and hence, its selection as a target molecule for regulation of CL function and for many beneficial processes involved in anti-carcinogenic properties can be thought of.

The metabolic hormones ghrelin, growth hormone, and insulin-like growth factor I are influenced by developmental age, sex, and nutritional status in domestic and free-ranging species. However the role these hormones play has not previously been explored in sub-tropical/ tropical mammals. Furthermore, the seasonality of species with less dynamic environmental cues, such as the West Indian manatee, have not been studied. The West Indian manatee is and endangered species distributed in the southeastern United States and throughout the Caribbean basin, and its nutritional physiology is influenced by environmental factors. Understanding the hormone response to nutritional status in this species and its seasonality will enhance our knowledge of the links between season, nutrition, and life history. The purpose of this research is to understand the biology and seasonal patterns of metabolic hormones in free-ranging manatees which will allow us to assess the nutritional status of wild populations. The research objectives include validation assays to accurately quantify hormone concentrations in manatees. Hormones were quantified in manatee serum using heterologous radioimmunoassay. Hormones were then evaluated between summer, fall, and winter and compared to body composition. Developmental patterns were also assessed. Lastly, hormones were examined between Florida and Antillean manatee populations. Manatees exhibited differences in GH, IGF-I, and body composition demonstrating seasonality similar to other species. Manatees exhibited differences between age classes suggesting decreased growth rate as the animals age. Differences were detected between populations. This research suggests that ghrelin, GH, and IGF-I can be used to indicate nutritional status and detect seasonality and developmental age in the manatee. This could prove to be a valuable tool in rehabilitation facilities and during captures and health assessments to provide better veterinary care and further improve overall health and body condition to better manage the survival of the species.

Both diabetes and behavioral health disorders (mental and substance use disorders) are significant health issues in the United States. While previous studies have shown worse health outcomes in people with diabetes and co-occurring behavioral health disorders (BHDs) than those with diabetes alone, it is unclear whether the quality of diabetes care was poorer in the presence of co-occurring BHDs. Although previous research has observed a trend of positive outcomes in people with comprehensive diabetes care, there is a lack of evidence about whether that mode of care delivery can improve outcomes in people with co-occurring BHDs. Therefore, further studies are necessary. Using a combined dataset from Medicare and Medicaid claims for Massachusetts residents, this study compared the quality of diabetes care (e.g., having at least 1 hemoglobin A1c test) and diabetes outcomes (e.g., eye complications) among Medicare and Medicaid beneficiaries with diabetes and co-occurring BHDs to those with diabetes alone in Massachusetts in 2005. The results showed a mixed picture on the relationships between BHDs and diabetes outcomes. While substance use disorders had adverse impact on adherence to quality measures (e.g., 20% less likely to attain full adherence, p0.05). Findings from this dissertation research suggest that disparities exist in the quality of diabetes care and health outcomes between people with substance use disorders and those without. The mode of care delivery needs to be further examined so that interventions can be designed to improve the outcomes of people with diabetes.

Introduction: Ventricular arrhythmias (VAs) are common after an acute coronary syndrome (ACS) and are associated with worse clinical outcomes. However, little is known about recent trends in their occurrence, their association with serum glucose levels, and their psychological impact in ACS setting. Methods: We examined 25-year (1986-2011) trends in the incidence rates (IRs) and hospital case-fatality rates (CFRs) of VAs, and the association between serum glucose levels and VAs in patients with an acute myocardial infarction (AMI) in the Worcester Heart Attack Study. Lastly, we examined the relationship between in-hospital occurrence of VAs and 12-month progression of depression and anxiety among hospital survivors of an ACS in the longitudinal TRACE-CORE study. Results: We found the IRs declined for several major VAs between 1986 and 2011while the hospital CFRs declined in both patients with and without VAs over this period. Elevated serum glucose levels at hospital admission were associated with a higher risk of developing in-hospital VAs. Occurrence of VAs, however, was not associated with worsening progression of symptoms of depression and/or anxiety over a 12-month follow-up period in patients discharged after an ACS. Conclusions: The burden and impact of VAs in patients with an AMI has declined over time. Elevated serum glucose levels at hospital admission may serve as a predictor for in-hospital occurrence of serious cardiac arrhythmias. In-hospital occurrence of VAs may not be associated with worsening progression of symptoms of depression and anxiety in patients with an ACS.

To survive, animals must adapt to a complex and challenging world in a way that is flexible and responsive, while maintaining internal homeostasis. Neuromodulators provide a means to systemically alter behavioral or physiological state based on intrinsic or extrinsic cues, however dysregulated neuroendocrine signaling has negative consequences for fitness and survival. Here I examine neuroendocrine function and dysfunction using the escape response in Caenorhabditis elegans. The RFamide neuropeptide FLP-18 is a co-transmitter with the monoamine tyramine and functions both synergistically and antagonistically to tyramine in coordinating escape behavior. Using behavioral analysis and calcium imaging, I show that FLP-18 functions primarily through the G-protein coupled receptor (GPCR) NPR-5 to increase calcium levels in muscle, enhancing locomotion rate, bending and reversal behavior during the escape response. Furthermore, I examine the relationship between persistent acute stress and resilience using repeated activation of the escape response as a model of neuroendocrine dysregulation. Repeated activation of the escape response shortens lifespan and renders animals more susceptible to thermal, oxidative, and nutritional stress. Tyramine release is necessary and sufficient for this effect and activity of the tyraminergic RIM neurons is differentially regulated by acute versus long-term stressors. Impaired stress resistance requires both the GPCR TYRA-3 in the intestine and intestinal neuropeptide release. Activation of the insulin receptor DAF-2 is downstream of TYRA-3 and inhibits the transcription factors DAF-16/FOXO, SKN-1/Nrf2 and HSF-1, linking monoamine signaling in acute stress to the insulin signaling pathway and impaired resilience to long-term stressors.

No description available.

The studies in this dissertation were designed to investigate the impacts of estrogen (17-β estradiol/E2) and moderate-intensity exercise (MIE) on the mesenteric arterial (MA) function of the University of California Davis type-2 diabetes mellitus (UCD-T2DM) Rat model. Our recent report suggests that diabetes impairs MA vasorelaxation in both sexes of the UCD-T2DM model. Particularly, we reported that MA from prediabetic male rats showed a greater impairment compared to that in prediabetic females. However, when females become diabetic, they exhibit a greater vascular dysfunction than males. Therefore, the aim of the first study was to investigate whether female sex hormone, specifically E2, preserves the MA vasorelaxation in female UCD-T2DM rats at the early prediabetic state. For this study, age-matched healthy Sprague Dawley (SD) and prediabetic female UCD-T2DM rats were ovariectomized and subcutaneously implanted with either a placebo or E2 pellet for 45 days. Regular aerobic exercise is a well-known therapeutic intervention for endothelial dysfunction, insulin resistance, and cardiovascular disease (CVD) risk in diabetes. However, there are still debates about the duration, intensity, and underlying mechanisms of benefits of exercise against deleterious metabolic consequences in diabetic patients. In the second study outlined in this dissertation, we examined the impact of exercise training on vascular function and wall structure of the UCD-T2DM male rats. Age-matched male diabetic and SD control rats were randomly divided into sedentary and exercise-trained groups. The exercise-trained groups ran on a treadmill for eight weeks (1hr/day, 5days per week). For both studies (Studies I & II), metabolic parameters and MA responses to vasodilator and vasocontractile agents were determined. Furthermore, the expression of molecules associated with vascular signaling were also analyzed. The specific aims of our studies were to investigate whether E2 and moderate-intensity exercise (MIE) alter the 1) endothelium-dependent vasorelaxation (EDV) and vasoconstriction 2) relative contribution of endothelium-derived relaxing factors (EDRF) to vasorelaxation, and 3) expression of proteins associated with vascular signaling, in MA of UCD-T2DM rats. In the first study, we demonstrated that acetylcholine (ACh)-induced vasorelaxation was impaired in MA of ovariectomized (OVX) prediabetic UCD-T2DM rats. Our data also showed that E2 replacement improved MA relaxation in OVX prediabetic group to a similar level to that in control groups. Inhibition of cyclooxygenase (COX) by indomethacin (Indo) did not significantly affect the vascular responses in any groups, suggesting a minor role of COX metabolites in MA relaxation in the experimental groups. Inhibition of nitric oxide (NO) synthase (NOS) by L-NAME reduced vasorelaxation to ACh in control groups, but it did not completely abolish the vasorelaxation. We also showed that in control (healthy) groups, both NO and endothelium-derived hyperpolarizing factor (EDHF)-type relaxation were dominant in the MA relaxation of placebo and E2 treated rats. However, in prediabetic groups, L-NAME completely abolished the vasorelaxation, regardless of E2 treatment, suggesting a relative shift from EDHF-type relaxation to only NO-mediated relaxation in these groups. Furthermore, the sensitivity of MA to NO was significantly impaired in OVX prediabetic group, but E2 treatment enhanced the MA sensitivity to NO. Overall, our data suggest that a greater vasorelaxation in the E2 treated OVX prediabetic group could be partly attributed to the elevated role of NO or improved sensitivity of MA to NO in this group. The second study demonstrated that ACh-induced vasorelaxation of MA was significantly impaired in sedentary diabetic (DS) male rats. MIE significantly enhanced MA vasorelaxation in the exercise-trained diabetic (DE) group compared to the DS. However, no significant differences were observed between the vasorelaxation of control sedentary (CS) and control exercise-trained groups (CE). Inhibition of COX enhanced maximal vasorelaxation response (Rmax) to ACh in DS arteries suggesting an elevated contractile COX contribution in MA of this group which could possibly be due to the observed increase in COX expression in the DS group. Unlike the DS group, inhibition of COX did not affect the vasorelaxation responses to ACh in the DE group. The addition of L-NAME resulted in a reduction in ACh-induced relaxation of MA from both DS and DE groups. However, the effect of L-NAME was more prominent in the DS group compared to the DE group, suggesting a major contribution of NO in DS arteries. On the other hand, a preserved role of NO with an enhanced EDHF-mediated relaxation was observed in the MA vasorelaxation of the DE group. Our data on the elevated small conductance calcium-activated potassium channel (SKCa) expression level in MA taken from the DE group compared to that in the DS group may suggest a role for SKCa in increased EDHF-type relaxation in the DE group. Furthermore, DS arteries exhibited a higher contractile response, myogenic tone, and wall thickness than those in MA of DE. Overall, our data suggest that MIE reduced myogenic tone (DE vs. DS) and improved EDV in mesenteric arteries of diabetic rats, possibly via a shift from contractile COX activity to both NO and EDHF-type relaxation. In conclusion, the data generated in study-I suggest that estrogen may protect prediabetic female MA from early vascular dysfunction, possibly by elevating the contribution of NO to vasorelaxation as a compensatory mechanism to the loss of EDHF-type relaxation in this group. Although the results of the current study are in agreement with our previous report demonstrating a possible protective effect of female sex hormones in the MA function at prediabetic state, additional studies are needed to establish the specific role of E2 in the progression of vascular dysfunction in the diabetic state. Lastly, an intriguing observation of study-II was that MIE improved vasorelaxation and prevented the loss of EDHF-type relaxation in diabetic arteries. This was in addition to the changes induced to the wall thickness and myogenic tone in arteries of UCD-T2DM males. Given that sex differences play an important role in cardiovascular physiology, additional studies are needed to establish the specific role of MIE on vascular dysfunction in UCD-T2DM female rats and its underlying mechanisms.

Bakgrund: Diabetes mellitus typ II är en av de snabbast växande sjukdomarna i världen. Det är en kronisk endokrin sjukdom som kräver många livsförändringar och determination. Det kännetecknas främst av att bukspottkörteln producerar otillräckligt med insulin. Den främsta orsaken till diabetes typ II inkluderar riskfaktorer som ärftlighet, ohälsosam livsstil avseende dålig kost, fysisk inaktivitet, fetma och ålder. Tidiga symtom på diabetes typ II är ökad törst, frekvent urinering, trötthet och muntorrhet. Syfte: Syftet var att belysa sjuksköterskors upplevelser av att vårda patienter med diabetes mellitus typ II. Metod: En litteraturstudie baserad på 10 kvalitativa artiklar som kritiskt analyserades och sammanfattades. Sökningar som härrörde från relevanta sökord gjordes i databaserna PubMed och Cinahl. Detta bidrog till att finna relevanta studier som genomförts i olika världsdelar samt kvalitetsgranskades. Resultat: Resultatet visade att majoriteten av sjuksköterskorna upplevde  bristande strategi och oförmåga att informera patienterna gällande livsstilsförändringar. Sjuksköterskorna upplevde även att patienterna var beroende av dem och såg egenvården som en utmaning. Resultatet visade även att personcentrerad vård var avgörande för att ge effektiv vård och förbättra patienternas deltagande.  Slutsats: Sjuksköterskor behöver mer kunskap, kompetens samt organisatoriska förutsättningar, för att ge en effektiv personcentrerad vård med behandling som stödjer en person som lever med diabetes typ II. Sjuksköterskor önskade mer kunskap inom kulturella och socioekonomiska faktorer för att ge optimal vård och stärka patientens förmåga. Brist på effektivt samarbete mellan vårdpersonal inom diabetesvården identifierades också som ett hinder för god vård. / Background: Diabetes mellitus type II is one of the fastest growing disease worldwide. It is a chronic endocrine disease that requires a lot of life changes and determination. It is characterized primarily by the pancreas producing insufficient insulin. The main cause of diabetes type II includes risk factors such as heredity and unhealthy lifestyle regarding poor diet, physical inactivity, obesity and age. Early symptoms of diabetes type II are increased thirst, frequent urinary, fatigue and dry mouth. Aim: The purpose was to explore nurses´ perception in caring of patients with diabetes mellitus type II. Method: A literature review of which 10 qualitative articles were critically analyzed and summarized. Searches derived from relevant keywords were made in PUBMED and CINAHL databases. This contributed to the finding of relevant articles that were conducted worldwide and were quality-reviewed.  Result: The articles acknowledged  that the majority of the nurses perceived a lack of strategy and inability to inform patients about lifestyle changes. The result also showed that person-centered care was crucial in order to provide effective care and improve patient participation. Conclusion: Nurses need more knowledge, competence and organizational conditions in order to provide effective person-centered care with treatment that supports a person living with type II diabetes. Nurses  also required more knowledge within cultural and social economic factors in order to provide optimal care and strengthen the patient’s abilities. Lack of effective collaboration between healthcare professionals in diabetes care was also identified as an obstacle to provide good care.

Bakgrund: Diabetes Mellitus typ I är ett globalt hälsoproblem som skördar många liv varje år och påverkar livskvaliteten för de drabbade. Diabetes typ I är en autoimmun sjukdom som leder till destruktion av insulinproducerande betaceller i pankreas och således rubbad glukosreglering. Huvudsakliga patogena immunceller inkluderar autoantikroppar, exempelvis riktade mot glutaminsyra dekarboxylase 65, och autoreaktiva T-celler. Diagnos sker generellt baserat på förhöjda halter plasmaglukos och eventuellt stimulering av C-peptid för att utreda status för den endogena betacellsfunktionen. Diabeteskomplikationer är en vanlig dödsorsak hos diabetespatienter. År 2019 orsakades 4,2 miljoner dödsfall av diabetes eller diabeteskomplikationer. I dagsläget är administrering av exogent insulin enda behandlingsmöjligheten för typ I diabetespatienter. Det har dock länge forskats på alternativ i form av preventiv behandling men i dagsläget finns inga preventiva behandlingar på marknaden. Syfte: Litteraturstudiens syfte var att undersöka prospektiva möjligheter till diabetespreventiv behandling inom områdena glutaminsyra dekarboxylase 65 vaccin och coxsackievirus B vaccin med avseende på effekt samt jämföra dessa två prospektiva behandlingsmöjligheter. Metod: Arbetet har utförts genom granskning av artiklar från databasen PubMed. För litteraturgranskning av studier om GAD-behandling valdes tre kliniska studier utifrån sökning med ”type 1 diabetes”, ”diabetes mellitus”, ”type 1”, ”GAD” och ”vaccine” som sökord. För artiklar om CVB och CVB-vaccin användes ”type 1 diabetes”, ”vaccine” och ”coxsackievirus” som sökord. Resultat: Kliniska studier på GAD-behandling visar ingen signifikant skillnad mellan GAD-alum och placebo i helgruppsanalyser. Vid vissa stratifierade analyser för exempelvis kön, ålder, eller antal riskfaktorer detekteras signifikanta skillnader genom ökad mängd stimulerad C-peptid eller progression till klinisk diabetes. Den prospektiva kohortstudien över diabetesincidens påvisar att CVB är en riskfaktor för diabetes hos människa. Vidare visar de prekliniska studierna på signifikant minskad diabetesincidens i CVB-vaccinerade studiepopulationer jämfört med placebo. Slutsats: Varken behandling med GAD-alum eller CVB-vaccin är möjligt att använda som preventiv behandling i nuläget. Dock visar studierna på lovande framtidsmöjligheter för CVB-vaccin som primärprevention och GAD-alum som sekundär- eller tertiärprevention. / Background: Diabetes Mellitus type I is a global health issue, causing numerous deaths each year and also influencing the quality of life of those affected. Type I diabetes is an autoimmune disease where the individuals own immune system causes destruction of insulin producing beta cells in the endocrine islets of pancreas. Main immunological features include, autoantibodies directed towards glutamic acid decarboxylase 65, and autoreactive T-cells. Diagnosis is generally based on elevated levels of plasma glucose and stimulated C-peptide, together disclosing the status of the beta cell function. The lack of endogen insulin causes disturbances in the glucose metabolism which leads to prevailing tissue damage in cells and organs of the diabetic individual’s body. Furthermore, insufficient control of plasma glucose is related to development of diabetes complications. Diabetic complications are known to be a major cause of death in diabetic patients. Diabetes and diabetic complications caused 4,2 million deaths in 2019. Insufficient adherence to treatment regimen during a long period of time is known to increase the risk for some common diabetes complications. Administration of exogenous insulin is the only current treatment available for type I diabetes, albeit recurrent attempts to find a cure or successful preventive treatment for diabetes mellitus type I. Recent promising research on diabetes preventive treatment includes the autoantigen glutamic acid decarboxylase-65 and vaccine against coxsackievirus B. Aim: The purpose of this literature study was to examine prospective possibilities for diabetes preventive treatments. Further, the purpose was to compare the promising preventive treatments of GAD65-vaccine and CVB-vaccine concerning effect and prospective treatment regimens. Methods: The thesis is a literature study based on articles found by searching the database PubMed. Clinical studies examining the effect of GAD-treatment was found by using key words such as ”type 1 diabetes”, ”diabetes mellitus”, ”type 1”, ”GAD” and ”vaccine”. Studies examining the effect of CVB and CVB-vaccines was primarily preclinical and prospective cohort studies, found by searching for the key words ”type 1 diabetes”, ”vaccine” and ”coxsackievirus”. Results: Clinical studies of GAD-treatment does not demonstrate a statistically significant difference between treatment with GAD-alum compared to placebo in full group analysis. Stratified groups occasionally prove significant differences in quantity of stimulated C-peptide or progression to clinical diabetes by age, gender or amount of risk factors for example. The prospective cohort study examining the incidence of diabetes, demonstrates that CVB is a risk factor for type I diabetes in humans. Furthermore, the preclinical studies detect a significant decrease in diabetes incidence in CVB-vaccinated mice compared with placebo. Conclusion: Neither treatment with GAD-alum nor CVB-vaccine is currently ready for use. However, the studies show a promising prospective possibility for CVB-vaccine as a primary prevention and GAD-alum as a secondary or tertiary prevention of type I diabetes.