Hyperglycemia induced testicular damage in type 2 diabetes mellitus rats exhibiting microcirculation impairments associated with vascular endothelial growth factor decreased via PI3K/Akt pathway

BRD7 facilitates ferroptosis via modulating clusterin promoter hypermethylation and suppressing AMPK signaling in diabetes-induced testicular damage

BACKGROUND

Diabetes mellitus (DM)-induced testicular damage is associated with sexual dysfunction and male infertility in DM patients. However, the pathogenesis of DM-induced testicular damage remains largely undefined.

METHODS

A streptozotocin (STZ)-induced diabetic model and high glucose (HG)-treated in vitro diabetic model were established. The histological changes of testes were assessed by H&E staining. Serum testosterone, iron, MDA and GSH levels were detected using commercial kits. Cell viability and lipid peroxidation was monitored by MTT assay and BODIPY 581/591 C11 staining, respectively. qRT-PCR, immunohistochemistry (IHC) or Western blotting were employed to detect the levels of BRD7, Clusterin, EZH2 and AMPK signaling molecules. The associations among BRD7, EZH2 and DNMT3a were detected by co-IP, and the transcriptional regulation of Clusterin was monitored by methylation-specific PCR (MSP) and ChIP assay.

RESULTS

Ferroptosis was associated with DM-induced testicular damage in STZ mice and HG-treated GC-1spg cells, and this was accompanied with the upregulation of BRD7. Knockdown of BRD7 suppressed HG-induced ferroptosis, as well as HG-induced Clusterin promoter methylation and HG-inactivated AMPK signaling in GC-1spg cells. Mechanistical studies revealed that BRD7 directly bound to EZH2 and regulated Clusterin promoter methylation via recruiting DNMT3a. Knockdown of Clusterin or inactivation of AMPK signaling reverses BRD7 silencing-suppressed ferroptosis in GC-1spg cells. In vivo findings showed that lack of BRD7 protected against diabetes-induced testicular damage and ferroptosis via increasing Clusterin expression and activating AMPK signaling.

CONCLUSION

BRD7 suppressed Clusterin expression via modulating Clusterin promoter hypermethylation in an EZH2 dependent manner, thereby suppressing AMPK signaling to facilitate ferroptosis and induce diabetes-associated testicular damage.

Molecular insights into Sertoli cell function: how do metabolic disorders in childhood and adolescence affect spermatogonial fate?

Male infertility is a major public health concern globally with unknown etiology in approximately half of cases. The decline in total sperm count over the past four decades and the parallel increase in childhood obesity may suggest an association between these two conditions. Here, we review the molecular mechanisms through which obesity during childhood and adolescence may impair future testicular function. Several mechanisms occurring in obesity can interfere with the delicate metabolic processes taking place at the testicular level during childhood and adolescence, providing the molecular substrate to hypothesize a causal relationship between childhood obesity and the risk of low sperm counts in adulthood.

Oral administration of proniosomal glibenclamide formulation protects testicular tissue from hyperglycemia fluctuations and ROS via Nrf2/HO-1 pathway

Type 2 diabetes causes high blood sugar due to insulin malfunction and is linked to male infertility. Using proniosomes can enhance the effectiveness of Glibenclamide, a medication that stimulates insulin secretion. In our study, male rats with diabetes were treated with GLB with or without proniosomal for 14 days. Proniosomal formulations maintained glucose levels prevented weight loss and showed normal testicular tissue. GLB-proniosomal reduces ROS caused by T2DM through Nrf2, HO-1 pathway and increases CAT, SOD, and GSH production in response to insulin and glucose uptake. The reference and proniosomal treatments showed CAT and SOD significant enzymatic elevation compared to the positive and negative control. CAT significantly correlated with Gpx4 expression with P = 0.0169 and r = 0.98; similarly, the enzymatic activity of SOD also showed a positive correlation between the average glucose levels (r = 0.99 and P = 0.0037). Intestinally, GSH analysis revealed that only proniosomal-GLB samples are significantly elevated from the positive control, with a P value of 0.0210. The data showed proniosomal-GLB was more effective than pure GLB, confirmed by higher Nrf2 (2.050 folds), HO-1 (2.148 folds), and GPx4 (1.9 folds) transcript levels relative to the control with less sample diversity compared to the reference samples, indicating proniosomal stabilized GLB in the blood. Administering GLB and proniosomes formulation has effectively restored testicular function and sperm production in diabetic rats by regulating ROS levels and upregulating anti-ROS in response to glucose uptake. These findings may lead to better treatments for diabetic patients who have infertility issues.

Causal relationship between genetically predicted type 2 diabetes mellitus and male infertility

Background

Diabetes mellitus (DM) stands as the most prevalent endocrine abnormality affecting the physiological systems and organs and impairing the male reproductive functions. Type 2 Diabetes Mellitus (T2DM), accounting for about 90-95% of DM, is closely associated with male infertility. However, the magnitude of the causal relationships between T2DM and male infertility remains unclear. The current investigation was to explore the causal relationship between T2DM and male infertility utilizing the Mendelian Randomization (MR) analysis.

Methods

A two-sample MR (2SMR) analysis was conducted to investigate the causal relationship between T2DM and male infertility in the European population from the genome-wide association study (GWAS) summary data that was publicly accessible. GWAS for T2DM and male infertility were extracted from the IEU Open GWAS Project database, with the resulting data encompassing 680 cases and 72,799 controls as the outcome data. Five MR methods were employed for the 2SMR analyses, namely the MR-Egger, weighted median estimation (WME), weighted mode (WM), inverse-variance weighted (IVW), and simple mode. The primary analytical technique utilized in this study was the IVW method, and a multivariate MR analysis was executed to examine the potential mediating influences of T2DM on male infertility.

Results

Following were the odds ratios (ORs) and associated 95% CIs derived from IVW (fixed effects), MR-Egger, WM, WME, and simple mode approaches: 0.824 (95% CI 0.703-0.966), 0.726 (95% CI 0.527-1.001), 0.827 (95% CI 0.596-1.150), 0.841 (95% CI 0.654-1.082), and 0.875 (95% CI 0.544-1.405), respectively. The outcomes of the heterogeneity tests were P=0.378 and P=0.384, respectively, implying no heterogeneity. Egger-intercept outcomes were P=0.374, highlighting the absence of pleiotropy. The stability of the results was affirmed through the leave-one-out analysis. Notably, all F-values surpassed 10, indicating the absence of weak bias attributed to instrument variables(IVs).

Conclusions

This research furnishes evidence supporting a causal association between T2DM and male infertility. These insights offer a foundation for future investigations aiming to establish the association between genetically predicted T2DM and male infertility. These outcomes suggest the significance of active monitoring and proactive measures for preventing infertility in male individuals with T2DM. Furthermore, careful consideration is required for individuals of reproductive age to prevent and treat T2DM.

Naringin from sweet orange peel improves testicular function in high fat diet-induced diabetic rats by modulating xanthine oxidase/uric acid signaling and maintaining redox balance

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a metabolic disorder affecting many organs, including the testis. Naringin from orange peel extract (OPE) is a flavanone with fertility-enhancing properties. Hence, this study was designed to establish the effect of naringin on T2DM-induced testicular dysfunction. Thirty male (30) Wistar rats were randomized into five groups control, diabetes, diabetes + naringin, diabetes + OPE, and diabetes + metformin. The administrations were via the oral route and lasted for 28 days.

RESULTS

Naringin ameliorated T2DM-induced increase in FBS and decrease in serum insulin. It also abrogated T2DM-induced decrease in sperm quality, gonadotropin-releasing hormone, luteinizing hormone, follicle-stimulating hormone, testosterone, estradiol, prolactin, catalase, superoxide dismutase, and total antioxidant capacity. Furthermore, naringin prevented a T2DM-induced increase in malonaldehyde, tumor necrosis factor-alpha, C-reactive protein, xanthine oxidase (XO), and uric acid (UA), it was accompanied by the restoration of normal testicular histoarchitecture.

CONCLUSIONS

Naringin prevented T2DM-induced testicular dysfunction by modulating XO/UA and restoring redox balance. Also, while the animals treated with OPE exhibited better ameliorative effects than their counterparts treated with naringin, the findings from this study showed that naringin would be a promising supplement for treating T2DM-induced male infertility.

Structural changes in testes of Streptozotocin induced diabetic rats and possible protective effect of royal jelly: light and electron microscopic study

Diabetes mellitus (DM) is one of the most common metabolic diseases causing damage in many organs in the body including the testes. Royal Jelly (RJ) is one of the honey bee products that has antioxidant, anti-inflammatory and antidiabetic properties. This study was performed to evaluate the changes in the microscopic structure of the testes in Streptozotocin (STZ)-induced diabetic rats, and the possible protective role of RJ. 60 adult male albino rats were divided into three groups. Group I Control group, Group II STZ group, and Group III STZ+RJ group. Group II received a single dose of STZ (50 mg/kg) by intraperitoneal injection. Group III received a single dose of STZ as in the second group then received RJ orally by intragastric tube in dose of (100 mg/kg/day) for 4 weeks after confirmation of diabetes. Light and electron microscopic studies were performed. Group II revealed marked structural changes affecting seminiferous tubules with sever reduction in germinal epithelium and loss of mature spermatozoa in their lumina. The interstitial tissue revealed degenerated Leydig cells and congested blood vessels. Mallory trichrome stained section of group II revealed marked increase in the amount of collagen fibers. Group III revealed highly preserved testicular architecture almost near to that appeared in the control group except few tubules that were damaged. In conclusion, RJ protected the testicular structure from the damaging effect of diabetic oxidative stress through its antioxidant effect thus preserving male fertility.

Erythritol attenuates testicular dysfunction in diabetic rat via suppression of oxidative stress, inflammation and apoptosis

Hyperglycemia -induced oxidative stress and inflammation have been closely associated with diabetes complications including testicular dysfunction. Conversely, reducing blood glucose and/or use of antioxidant have been associated with reduced diabetes complications. The present study investigated the effect of erythritol (which has both antioxidant and blood glucose lowering function) on diabetes -induced testicular dysfunction in rats. Thirty male Wistar rats (170-200g) were randomly divided into 5 groups: 1) control; 2) erythritol; 3) diabetic; 4) diabetic + erythritol 1000 mg/kg; and 5) diabetic + metformin 300 mg/kg. After 8 weeks of treatment period, blood sample, testes and epididymis were collected for reproductive hormones, biochemical and histological examinations, and sperm analysis respectively. There was a significant (p < 0.05) decrease in sperm count, sperm motility, sperm morphology and serum reproductive hormones (Follicle stimulating hormone (FSH), Leutinizing hormone (LH), testosterone and gonadotropin releasing hormone (GnRH)) of diabetes rat compared to control. Also, diabetes rat showed increase in sperm and testicular malonaldehyde (MDA) and decrease in sperm and testicular superoxide dismutase (SOD) activity and glutathione (GSH) level. Further, diabetes rat showed reduced testicular weight, decreased testicular 17β-HSD and 3β-HSD activity and testicular histo-architectural alteration which were accompanied by decrease testicular vascular endothelial growth factor (VEGF) and concomitant increase in testicular myeloperoxidase activity and level of caspase 3. The present results indicates that induction of diabetes in rat causes reduction in the level of reproductive hormones (Testosterone, LH and FSH) as well as sperm and testicular oxidative stress causing abnormal sperm parameters, and biochemical and histo-architectural alterations in the testes of rats. In addition, the present results suggest that erythritol administration reduced blood glucose and ameliorated hyperglycemia -induced oxidative stress -mediated alterations in both sperm and testes of diabetes rat. Further, the present study suggests that erythritol improved testicular oxidative stress, inflammation and apoptosis by up-regulating VEGF.

CysLTR1 antagonism by montelukast can ameliorate diabetes-induced aortic and testicular inflammation

AIMS

Montelukast, a cysteinyl leukotriene receptor (CysLTR)1 antagonist, is emerging as an attractive strategy to curtail diabetic complications; however, its role in aortic and testicular tissues is unknown. This study investigated the effect of CysLTR1 antagonism by montelukast on toll-like receptor (TLR)4 and nuclear factor kappa B (NF-κB) pathways in diabetes-induced aortic and testicular injury.

METHODS

Adult male Sprague-Dawley rats were made diabetic with Streptozotocin (STZ, 55 mg/kg). Following this, Streptozotocin-induced diabetic (SD) rats were administered montelukast (10 and 20 mg/kg, orally) for 8 weeks. Blood glucose, serum malondialdehyde (MDA), inflammatory markers, and histopathology were evaluated.

RESULTS

Montelukast showed protection against diabetic complications, as evidenced by the ameliorative effect against STZ-induced alterations in oxidative stress as indicated by serum MDA levels. Moreover, montelukast conferred a significant decrease in the aortic and testicular levels of CysLTR1, TLR4, and NF-κB with a subsequent decrease in the levels of NOD-like receptor family pyrin domain containing (NLRP)3, caspase 1, interleukin (IL)-1β, IL-6, monocyte chemoattractant protein (MCP)-1, and tumor necrosis factor (TNF)-α. Additionally, administration of montelukast resulted in autophagy stimulation, as shown by decreased p62/Sequestosome (SQSTM)1 levels. Finally, montelukast protection resulted in normal thickness of whole aortic wall, regular tunica (t.) intima, mild vacuolation of smooth muscle fibers in aorta, increased size of seminiferous tubules, and increased spermatogenesis in testis as demonstrated by histopathology.

CONCLUSIONS

The protective effect of montelukast against diabetes-induced aortic and testicular injury is due to its antioxidant, anti-inflammatory, and autophagy stimulation characteristics.

Combination Therapy with Enalapril and Paricalcitol Ameliorates Streptozotocin Diabetes-Induced Testicular Dysfunction in Rats via Mitigation of Inflammation, Apoptosis, and Oxidative Stress

BACKGROUND

As the impacts of diabetes-induced reproductive damage are now evident in young people, we are now in urgent need to devise new ways to protect and enhance the reproductive health of diabetic people. The present study aimed to evaluate the protective effects of enalapril (an ACE inhibitor) and paricalcitol (a vitamin D analog), individually or in combination, on streptozotocin (STZ)-diabetes-induced testicular dysfunction in rats and to identify the possible mechanisms for this protection.

MATERIAL AND METHODS

This study was carried out on 50 male Sprague-Dawley rats; 10 normal rats were allocated as a non-diabetic control group. A total of 40 rats developed diabetes after receiving a single dose of STZ; then, the diabetic rats were divided into four groups of equivalent numbers assigned as diabetic control, enalapril-treated, paricalcitol-treated, and combined enalapril-and-paricalcitol-treated groups. The effects of mono and combined therapy with paricalcitol and enalapril on testicular functions, sperm activity, glycemic state oxidative stress, and inflammatory parameters, as well as histopathological examinations, were assessed in comparison with the normal and diabetic control rats.

RESULTS

As a result of diabetes induction, epididymal sperm count, sperm motility, serum levels of testosterone, follicle-stimulating hormone (FSH) as well as luteinizing hormone (LH), and the antioxidant enzyme activities, were significantly decreased, while abnormal sperm (%), insulin resistance, nitric oxide (NO), malondialdehyde (MDA), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were significantly increased, along with severe distortion of the testicular structure. Interestingly, treatment with paricalcitol and enalapril, either alone or in combination, significantly improved the sperm parameters, increased antioxidant enzyme activities in addition to serum levels of testosterone, FSH, and LH, reduced insulin resistance, IL-6, and TNF-α levels, and finally ameliorated the diabetes-induced testicular oxidative stress and histopathological damage, with somewhat superior effect for paricalcitol monotherapy and combined therapy with both drugs compared to monotherapy with enalapril alone.

CONCLUSIONS

Monotherapy with paricalcitol and its combination therapy with enalapril has a somewhat superior effect in improving diabetes-induced testicular dysfunction (most probably as a result of their hypoglycemic, antioxidant, anti-inflammatory, and anti-apoptotic properties) compared with monotherapy with enalapril alone in male rats, recommending a synergistic impact of both drugs.

Modulatory effect of liraglutide on doxorubicin-induced testicular toxicity and behavioral abnormalities in rats: role of testicular-brain axis

Doxorubicin (DOX) is a powerful chemotherapeutic agent used in many types of malignancies. However, its use results in testicular damage. DOX-induced testicular damage results in low level of serum testosterone which may affect cognitive function. The current study investigated the protective effect of liraglutide (50, 100 μg/kg/day) in testicular toxicity and the consequent cognitive impairment induced by DOX. DOX treatment reduced sperm count (62%) and sperm motility (53%) and increased sperm abnormalities (786%), as compared to control group. DOX also reduced serum testosterone level (85%) and the gene expression of testicular 3β-HSD (68%) and 17β-HSD (82%). Moreover, it increased testicular oxidative stress (MDA and GSH) by 103% and 59%, respectively, apoptotic (caspase-3 and P53) by 996% and 480%, respectively. In addition, DOX resulted in increasing autophagic markers including PAKT, mTOR, and LC3 by 48%, 56%, and 640%, respectively. Additionally, rats' behavior in Y-maze (60%) and passive avoidance task (85%) was disrupted. The histopathological results of testis and brain supported the biochemical findings. Treatment with liraglutide (100 μg/kg/day) significantly abrogated DOX-induced testicular damage by restoring testicular architecture, increasing sperm count (136%) and sperm motility (106%), and decreasing sperm abnormalities (84%) as compared to DOX group. Furthermore, liraglutide increased serum testosterone (500%) and steroidogenesis enzymes 3β-HSD (105%) and 17β-HSD (181%) along with suppressing oxidative stress (MDA and GSH) by 23% and 85%, respectively; apoptotic (caspase-3 and P53) by 59% and55%, respectively; and autophagic markers including PAKT, mTOR, and LC3 by 48%, 97%, and 60%, respectively. Moreover, it enhanced the memory functions in passive avoidance and Y-maze tests (132%). In conclusion, liraglutide is a putative agent for protection against DOX-induced testicular toxicity and cognitive impairment through its antioxidant, antiapoptotic, and antiautophagic effects.

Consequences of Type-2 diabetes mellitus and Malaria co-morbidity on sperm parameters in men; a case-control study in a district hospital in the Ashanti Region of Ghana

Type-2 diabetes mellitus (T2DM) and malaria infection are highly prevalent in Africa particularly, in the Sub-Saharan Region. A greater number of people in the Ghanaian population who have T2DM are also reported to harbor malaria parasites. This study aimed to investigate the influence of T2DM & Malaria co-morbidity on sperm parameters among patients in the Ashanti Region of Ghana. This hospital-based cross-sectional analytic case-control study comprised 254 adult male study participants comprising 80 T2DM & Malaria co-morbidity, 80 T2DM only, and 94 normal controls. A blood sample (10mL) was drawn from each participant to measure FBG, HbA1c levels, Testosterone levels, Total cholesterol, and determination of Malaria parasite density. Seminal fluid was also collected from each participant for semen analysis. Sperm kinetics of the T2DM & Malaria co-morbidity group particularly; total motility, rapid progressive motility, and slow progressive motility were negatively affected compared to both T2DM only (p<0.0001) and the Normal control (p<0.0001). Normal sperm morphology was significantly affected in the co-morbidity group compared to T2DM only (p<0.0001). Sperm vitality was also statistically significantly reduced in the T2DM & Malaria co-morbidity than in T2DM only (t (64) = -8.62; p<0.001). There was a significant decline in testosterone levels in the T2DM & Malaria co-morbidity group than in the T2DM only (p<0.0001) and the control (p <0.0001). In conclusion, T2DM and malaria infection have a stronger propensity to alter sperm morphology and lower sperm motility and vitality.

Forskolin Improves Male Reproductive Complications Caused by Hyperglycemia in Type 2 Diabetic Rats

BACKGROUND

In many diabetic patients, spermatogenesis complications are frequent causing infertility problems. This study aimed to demonstrate the effect of Forskolin on male reproductive dysfunction caused by type 2 diabetes.

MATERIALS AND METHODS

In this experimental study, type 2 diabetes was induced by a high-fat diet (HFD) for one month and then a low single dose injection (35 mg/kg) of streptozotocin (STZ) in Wistar rats. After 72 hours, rats with more than 200 mg/dl of blood glucose were considered type 2 diabetic rats. Forty rats (200-250 g) were divided into four groups (n=10) including group 1 (G1): rats with normal diet and buffer citrate (STZ solvent) injection, group 2 (G2): control type 2 diabetic rats with HFD and STZ injection, group 3 (G3): type 2 diabetic rats received phosphate buffer saline (PBS) as Forskolin solvent, and group 4 (G4): Forskolin treated diabetic rats (10 mg/kg) for 1 month.

RESULTS

In comparison to control group, in diabetic groups (G2 and G3) some parameters are increased significantly: The blood glucose (P=0.00078), testicular malondialdehyde (MDA) level and body weight (P=0.00009) and Bax gene expression (P=0.00007). Unlike, some parameters are decreased significantly: The serum level of testosterone (P=0.0009), testicular superoxide dismutase (SOD, P=0.00007) and glutathione peroxidase (GPX) levels (P=0.00008), sperm concentration (P=0.00008), motility (P=0.00009), normal morphological sperm (P=0.00008) and Bcl-2 gene expression (P=0.00009). However, in Forskolin treated group (G4) the parameters stayed close to control values that was significantly (P=0.00007) higher than in G2 and G3 groups. Therefore, treatment with Forskolin significantly improved these abnormal changes in Forskolin-treated group.

CONCLUSION

Our study demonstrates that Forskolin is an effective antidiabetic agent, which significantly improves sperm concentration, testosterone levels, and antioxidant activity in diabetic rats.

Liraglutide ameliorates diabetic-induced testicular dysfunction in male rats: role of GLP-1/Kiss1/GnRH and TGF-β/Smad signaling pathways

Introduction: Glucagon-like peptide -1 (GLP-1) is released by intestinal cells to stimulate glucose-dependent insulin release from the pancreas. GLP-1 has been linked to ameliorating obesity and/or diabetic complications as well as controlling reproductive function. Liraglutide is a GLP-1 receptor agonist (GLP-1RA) with 97% homology with GLP-1. The main objective of this study was to investigate the ameliorative role of liraglutide in diabetic-induced reproductive dysfunction in male rats. Methods: Rats were randomly allocated into 3 groups; a control group, a diabetic group, and a liraglutide-treated diabetic group. Results: In the diabetic group, a significant increase in BMI, FBG, HbA1c, HOMA-IR, TC, TAG, LDL, IL6, TNFα, and MDA, as well as decreased serum insulin, HDL, GSH, total testosterone, LH, and FSH, were shown compared to the control group. Furthermore, A significant downregulation in relative hypothalamic gene expression of GLP-1R, PPAR-α, PGC-1α, kiss, kiss1R, leptin, leptin R, GnRH GLP-1R, testicular PGC-1α, PPARα, kiss1, kiss1R, STAR, CYP17A1, HSD17B3, CYP19A, CYP11A1, and Smad7, as well as upregulation in hypothalamic GnIH and testicular TGF- β and Smad2 expression, were noticed compared to the control group. Liraglutide treatment significantly improved such functional and structural reproductive disturbance in diabetic rats. Conclusion: GLP-1RAs ameliorated the deleterious effects of diabetes on reproductive function by targeting GLP-1/leptin/kiss1/GnRH, steroidogenesis, and TGF- β/Smad pathways.

N6-Methyladenosine Methyltransferase METTL3 Alleviates Diabetes-Induced Testicular Damage through Modulating TUG1/Clusterin Axis

BACKGROUND

The present study investigated the regulatory effects of N6-methyladenosine (m6A) methyltransferase like-3 (METTL3) in diabetes-induced testicular damage.

METHODS

In vivo diabetic mice and high glucose (HG) treated GC-1 spg cells were established. The mRNA and protein expressions were determined by real-time quantitative polymerase chain reaction, Western blot, immunofluorescence and immunohistochemistry staining. Levels of testosterone, blood glucose, cell viability, and apoptosis were detected by enzyme-linked immunosorbent assay, MTT, and flow cytometry, respectively. Molecular interactions were verified by RNA immunoprecipitation and RNA pull-down assay. Histopathological staining was performed to evaluate testicular injury.

RESULTS

METTL3 and long non-coding RNA taurine up-regulated 1 (lncRNA TUG1) were downregulated in testicular tissues of diabetic mice and HG-treated GC-1 spg cells. METTL3 overexpression could reduce the blood glucose level, oxidative stress and testicular damage but enhance testosterone secretion in diabetic mouse model and HG-stimulated GC-1 spg cells. Mechanically, METTL3-mediated m6A methylation enhanced the stability of TUG1, then stabilizing the clusterin mRNA via recruiting serine and arginine rich splicing factor 1. Moreover, inhibition of TUG1/clusterin signaling markedly reversed the protective impacts of METTL3 overexpression on HG-stimulated GC-1 spg cells.

CONCLUSION

This study demonstrated that METTL3 ameliorated diabetes-induced testicular damage by upregulating the TUG1/clusterin signaling. These data further elucidate the potential regulatory mechanisms of m6A modification on diabetes-induced testicular injury.

Antioxidant, antiapoptotic, and antifibrotic abilities of L-Arginine ameliorate the testicular dysfunction in diabetic rats

Testicular dysfunction and infertility are serious complications of diabetes mellitus (DM). L-Arginine (L-Arg) is a semi essential amino acid with various biological and metabolic functions. The molecular mechanisms of L-Arg on testicular dysfunction caused by DM remain elusive. This study aimed to assess the potential protective effect of L-Arg in diabetic testis and its possible mechanisms. 24 adult male Wistar albino rats were randomly divided into four groups: CON, L-Arg that received 1 g/kg body weight of L-Arg orally for 4 weeks, DM that fed a high fat diet followed by an injection of 30 mg/kg streptozotocin intraperitoneally, and L-Arg-treated DM that were diabetic and administered L-Arg. DM decreased relative testicular weight, reduced serum testosterone, and impaired semen parameters. Reduced total antioxidant capacity (TAC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px), in addition to increased transforming growth factor B1 (TGF-β1) and nitric oxide (NO) levels, were found in the testicular tissue. This was associated with severe degenerative changes in the seminiferous tubules and interstitial cells of Leydig, reduction of Johnsen's score, significantly increased expression of both inducible nitric oxide synthase (iNOS) and caspase-3, and reduced zonula occludens (ZO)- 1 expression. Ultrastructurally, disrupted intercellular junctions and degeneration of interstitial cells of Leydig were observed. In contrast, treatment of diabetic animals with L-Arg increased TAC, SOD and GSH-Px, decreased TGF-β1 and NO levels, downregulated iNOS and caspase-3 expression, upregulated ZO-1 expression, and maintained the integrity of the Sertoli cell junctions. Hence, L-Arg restored the normal testicular structure and function via its antioxidant, antiapoptotic, and antifibrotic effects.

Diabetes-Induced Autophagy Dysregulation Engenders Testicular Impairment via Oxidative Stress

Testes produce sperms, and gamete generation relies on a proper niche environment. The disruption of hierarchical regulatory homeostasis in Leydig or Sertoli cells may evoke a sterile phenotype in humans. In this study, we recapitulated type 2 diabetes mellitus by using a high-fat diet- (HFD-) fed mouse model to identify the phenotype and potential mechanism of diabetes-induced testicular impairment. At the end of the study, blood glucose levels, testosterone structure, testicular antioxidant capacity, and testosterone level and the expression of hypoxia-inducible factor- (HIF-) 1α, apoptosis-related protein cleaved-caspase3, and autophagy-related proteins such as LC3I/II, p62, and Beclin1 were evaluated. We found that long-term HFD treatment causes the development of diabetes mellitus, implicating increased serum glucose level, cell apoptosis, and testicular atrophy (P < 0.05 vs. Ctrl). Mechanistically, the results showed enhanced expression of HIF-1α in both Sertoli and Leydig cells (P < 0.05 vs. Ctrl). Advanced glycation end products (AGEs) were demonstrated to be a potential factor leading to HIF-1α upregulation in both cell types. In Sertoli cells, high glucose treatment had minor effects on Sertoli cell autophagy. However, AGE treatment stagnated the autophagy flux and escalated cell apoptosis (P < 0.05 vs. Ctrl+Ctrl). In Leydig cells, high glucose treatment was adequate to encumber autophagy induction and enhance oxidative stress. Similarly, AGE treatment facilitated HIF-1α expression and hampered testosterone production (P < 0.05 vs. Ctrl+Ctrl). Overall, these findings highlight the dual effects of diabetes on autophagy regulation in Sertoli and Leydig cells while imposing oxidative stress in both cell types. Furthermore, the upregulation of HIF-1α, which could be triggered by AGE treatment, may negatively affect both cell types. Together, these findings will help us further understand the molecular mechanism of diabetes-induced autophagy dysregulation and testicular impairment, enriching the content of male reproductive biology in diabetic patients.

Potential Mechanism of Platelet-rich Plasma Treatment on Testicular Problems Related to Diabetes Mellitus

Diabetes mellitus is a condition of continuously increased blood glucose levels that causes hyperglycemia. This condition can result in disorders of various organs including testicular problems. The use of platelet-rich plasma (PRP) which is contained in several growth factors shows its potential in overcoming testicular problems. This literature review study was conducted to identify the potential of PRP in overcoming various testicular problems due to diabetic conditions.

Chitosan-Encapsulated Nano-selenium Targeting TCF7L2, PPARγ, and CAPN10 Genes in Diabetic Rats

This study investigates the antidiabetic and antioxidant potential of chitosan-encapsulated selenium nanoparticles in streptozotocin-induced diabetic model. Glibenclamide was used as a reference antidiabetic drug. Forty-eight adult male Wistar rats were used along the study and divided equally into 6 groups of (I) normal control, (II) chitosan-encapsulated selenium nanoparticles (CTS-SeNPs), (III) glibenclamide, (IV) streptozotocin (STZ), (V) STZ + CTS-SeNPs, and (VI) STZ + Glib. The animals were sacrificed on the 35th day of the experiment. Serum glucose, insulin, IGF-1, ALT, AST, CK-MB, oxidative stress, lipid profile, and inflammatory parameters were subsequently assessed. Also, the expression level of TCF7L2, CAPN10, and PPAR-γ genes were evaluated using qPCR. In addition, histopathological studies on pancreatic tissue were carried out. The results revealed that STZ induced both diabetes and oxidative stress in normal rats, manifested by the significant changes in the studied parameters and in the physical structure of pancreatic tissue. Oral administration of CTS-SeNPs or Glib results in a significant amelioration of the levels of serum fasting blood glucose, insulin, IGF-1, AST, ATL, and CK-MB as compared with STZ-induced diabetic rats. CTS-SeNPs and Glib diminished the level of lipid peroxidation, increased total antioxidant capacity level, as well as possessed strong inhibition against serum α-amylase and α-glucosidase activities. Diabetic animals received CTS-SeNPs, or Glib demonstrated a significant (p < 0.05) decrease in the expression level of TCF7L2 and CAPN10 genes with a significant increase in the expression level of PPAR-γ gene, compared to STZ group. The above findings clarify the promising antidiabetic and antioxidant effect of CTS-SeNPs, recommending its inclusion in the currently used protocols for the treatment of diabetes and in the prevention of its related complications.

Dose-dependent effects of taurine against testicular damage in a streptozotocin-induced type 1 diabetes mellitus rat model

OBJECTIVES

Testicular dysfunction has been associated with chronic hyperglycemia in diabetes mellitus patients. We investigated taurine's possible mechanisms and protective effects against testicular damage using a rat model of streptozotocin-induced diabetes.

METHODS

Wistar rats (N = 56) were divided into seven equal groups. Untreated control rats received saline, and treated control rats received taurine 50 mg/kg orally. To induce diabetes, rats received a single dose of streptozotocin. Metformin-treated diabetic rats received metformin at a dose of 300 mg/kg. Taurine-treated groups received 10, 25, or 50 mg/kg. All treatments were provided orally once a day for 9 weeks following the streptozotocin injection. Levels of blood glucose, serum insulin, cholesterol, testicular tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-1beta (IL-1β), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione (GSH), and catalase (CAT) were examined. Sperm count, progressive sperm motility, and sperm abnormalities were examined. Body and relative reproductive gland weights were assessed. Histopathological examinations of the testes and epididymis were performed.

RESULTS

Metformin as well as taurine (in a dose-dependent manner) resulted in significant improvements in body and relative reproductive gland weights, blood glucose, serum cholesterol, and insulin levels, as well as cytokine and oxidative parameters. These findings were associated with significant improvement in sperm count, progressive sperm motility, sperm abnormalities, and histopathological lesions in the testes and epididymis.

CONCLUSION

Taurine can potentially improve hyperglycemia, hypercholesterolemia, and testicular damage associated with diabetes mellitus, possibly by controlling inflammation and oxidative stress.

Dietary zinc deficient condition increases the Bisphenol A toxicity in diabetic rat testes

Bisphenol A (BPA) is a widely used endocrine disrupter that causes male reproductive dysfunction in humans and rodents. Diabetes-induced hyperglycemia alters spermatogenesis and antioxidant status, which negatively impacts male fertility in adults. Zinc (Zn) deficiency is a global health concern maintaining the testicular structure and functions in developing gonads. The present experiment was designed to investigate the role of Zn deficiency on BPA-induced germ cell and male gonadal toxicity in diabetic conditions. Rats were randomly divided into eight different groups - control (normal feed and water), BPA (10 mg/kg/day), ZDD (fed with a Zn-deficient diet), DIA (diabetic), BPA+ZDD, BPA+DIA, ZDD+DIA and BPA+ZDD+DIA for four weeks. Animals' body and organ weight, sperm count, motility and sperm morphology were examined; testes and epididymis histopathology were investigated. Testicular DNA damage and sperm apoptosis were evaluated by halo and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays respectively. Testicular catalase and octamer-binding transcription factor 4 (OCT4) expressions were evaluated by western blot analysis. The present results demonstrated that dietary Zn-deficient condition significantly increased the BPA-induced testicular, epididymal and sperm toxicity in diabetic rats due to hypogonadism, increased sperm abnormalities, epididymis, testicular structure and DNA damages, sperm apoptosis as well as decreased testicular catalase and OCT4 expressions. The present results revealed that dietary Zn-deficient condition exacerbated the BPA-induced testicular and epididymal toxicity as well as perturbed the general male reproductive health in diabetic rats.

Protective Effect of Portulaca oleracea on Streptozotocin-Induced Type I Diabetes-Associated Reproductive System Dysfunction and Inflammation

Background: Type-one diabetes (T1D), a chronic autoimmune disease with marked inflammatory responses, is associated with infertility complications and implications. Based on the anti-diabetic, antioxidant, and anti-hyperlipidemic potential of Portulaca oleracea (PO), this study aimed to evaluate the protective effect of this plant extract on streptozotocin-induced type-I-diabetes-associated reproductive system dysfunction and inflammation. Methods: Male rats were randomly divided into four experimental groups: control, diabetic, and treatment/s (PO extract at 100 or 300 mg/kg/daily). Then food and water consumption, body, testis and epididymis weights, histopathological evaluation, seminiferous tubules diameter, sperm count and motility, glucose levels, sex hormones, and inflammatory and oxidative stress markers were evaluated. Results: Our results showed that streptozotocin-induced diabetes significantly increased food and water consumption; increased glucose, MDA, TGF-β1, and TNF-α levels; and decreased the seminiferous tubules diameter, sperm count and motility, levels of LH, testosterone, total thiol, VEGF, and SOD activity. Interestingly, PO extract (phytochemically characterized by using liquid chromatography–mass spectrometry to detect bioactive molecules) significantly ameliorated these parameters and histopathological indexes’ damage in rats. Conclusion. Even if more preclinical assessments are needed to better characterize the mechanism/s of action, the results of this study will pave the way for the rational use of PO on diabetic-associated clinical complications and implications.

L-carnitine Attenuates DNA Damage and Oxidative Stress in Diabetic Animals

Background: Diabetes is a metabolic disorder characterized by high plasma glucose levels. In this disease, increased production of reactive oxygen species (ROS) results in DNA damage and multiple complications. L-carnitine (LC) has shown a potent antioxidant activity that may reduce oxidative stress. Objectives: This study aims at assaying the effect of LC on DNA damage in streptozotocin-induced diabetic rats and evaluating the changes in antioxidant markers and liver function enzymes after the administration of LC . Methods: In the present study, for induction of diabetes, we injected a single dose of streptozotocin (65 mg/kg) by the intraperitoneal route, and diabetic rats were treated with LC 200, 300, and 400 mg/kg daily for 3 weeks. We detected the DNA damage at 7, 14, and 21 days after induction diabetes by the comet assay method. The blood glucose level, plasma alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were tested. Also, we measured the activity levels of superoxide dismutase (SOD) and intracellular glutathione (GSH). Results: The results of this study demonstrated the increasing amount of DNA damage with the amount and duration of hyperglycemia. L-carnitine treatment significantly decreased the parameters of genotoxicity such as % DNA in the tail, tail length, and tail moment over time. Moreover, the treatment of diabetic rats with LC 300 and 400 mg/kg/day after 21 days led to a remarkable decrease in blood glucose than diabetic rats. Also, we observed that LC can ameliorate enzyme liver function and reduce oxidative stress via enhancement of GSH and SOD levels. Conclusions: The results of this study indicated the protective effect of LC against DNA damage and oxidative stress in diabetic rats.

Arthrospira platensis nanoparticles defeat against diabetes-induced testicular injury in rat targeting, oxidative, apoptotic, and steroidogenesis pathways

Varieties of studies have been used to investigate the health benefits of Spirulina (Arthrospira platensis); however, more research is needed to examine if its nano form may be utilized to treat or prevent several chronic diseases. So, we designed this study to explore the effect and the cellular intracellular mechanisms by which Arthrospira platensis Nanoparticles (NSP) alleviates the testicular injury induced by diabetes in male Wistar rats. Eighty Wistar male rats (n = 80) were randomly allocated into eight groups. Group 1 is untreated rats (control), Group 2 including STZ-induced diabetic rats with 65 mg/kg body weight STZ (STZ-diabetic), Group 3-5: including diabetic rats treated with NSP1, NSP2, and NSP3 at 0.25, 0.5, and 1 mg/kg body weight, respectively, once daily orally by the aid of gastric gavage for 12 consecutive weeks and groups 6-8 include normal rats received NSP (0.25, 0.5, and 1 mg/kg body weight once daily orally. The identical volume of normal saline was injected into both control and diabetic rats. After 12 weeks of diabetes induction, the rats were killed. According to our findings, NSP administration to diabetic rats enhances the total body weight and the weight of testes and accessory glands; in addition, NSP significantly reduced nitric oxide and malondialdehyde in testicular tissue improved sperm parameters. Intriguingly, it raises testicular GSH and SOD activity by a significant amount (p < 0.05). As well, Oral administration of NSP to diabetic rats resulted in a decrease in the blood glucose levels, HA1C, induced in the diabetic group, which overcame the diabetic complications NSP caused down-regulation of apoptotic genes with upregulation of BCL-2 mRNA expression (p < 0.05) and prominent up-regulation of steroidogenesis genes expression level in testes in comparison to the diabetic rats which resulted in improving the decreased levels of testosterone hormone, FSH, and LH induced by diabetes. In the same way, our histopathological findings support our biochemical and molecular findings; in conclusion, NSP exerted a protective effect against reproductive dysfunction induced by diabetes not only through its high antioxidant and hypoglycemic action but also through its down-regulation of Apoptotic genes and up-regulation of steroidogenesis regulatory genes expression level in diabetic testes.

Nicotinamide mononucleotide improves spermatogenic function in streptozotocin-induced diabetic mice via modulating the glycolysis pathway

Spermatogenic dysfunction is one of the major secondary complications of diabetes; however, the underlying mechanisms remain ill-defined, and there is no available drug or strategy for the radical treatment of diabetic spermatogenic dysfunction. Therefore, the objective of this study is to investigate the protective effects of nicotinamide mononucleotide (NMN) on testicular spermatogenic function in streptozotocin (STZ)-induced diabetic mice. The results show that oral administration of NMN significantly increases the body and testis weight and the number of sperms. Moreover, the abnormal sperm count and the rate of sperm malformation are significantly decreased compared with the saline-treated diabetic mice. Histological analysis reveals that NMN treatment significantly increases the area and diameter of seminiferous tubules, accompanied by an increased number of spermatogenic cells and sperms. Immunohistochemistry and qRT-PCR results show that NMN increases Bcl-2 expression and decreases Bax expression in the testis. NMN also increases the protein expression of Vimentin and the mRNA expressions of WT1 and GATA4. In addition, qRT-PCR, western blot analysis and immunohistochemistry results also show that NMN increases the expressions of glycolysis-related rate-limiting enzymes including HK2, PKM2, and LDHA. In summary, this study demonstrates the protective effects of NMN on the testis in an STZ-induced diabetic mice model. NMN exerts its protective effects via reducing spermatogenic cell apoptosis by regulating glycolysis of Sertoli cells in diabetic mice. This study provides an experimental basis for the future clinical application of NMN in diabetes-induced spermatogenic dysfunction.

The Herb Pair Radix Rehmanniae and Cornus Officinalis Attenuated Testicular Damage in Mice With Diabetes Mellitus Through Butyric Acid/Glucagon-Like Peptide-1/Glucagon-Like Peptide-1 Receptor Pathway Mediated by Gut Microbiota

Growing body of research indicates that Traditional Chinese Medicine (TCM) interact with gut microbiota (GM) after oral administration. Radix Rehmanniae and Cornus Officinalis (RR-CO), a well-known TCM pair, is often used to treat diabetes mellitus (DM) and its complications. The current study aimed to explore the protective effects of RR-CO on DM induced testicular damage by modulating GM. The RR-CO treatments significantly reduced hyperglycemia, ameliorated testicular ultrastructural damage and inflammation in DM model to varying degrees. Additionally, 16S-ribosomal DNA (rDNA) sequencing results showed that RR-CO treatment increased the amount of butyric acid-producing GM, such as Clostridiaceae_1 family, and decreased the abundance of Catabacter, Marvinbryantia, and Helicobacter genera. RR-CO fecal bacteria transplantation (RC-FMT) increased the abundance of Clostridiaceae_1 in the Model FMT (M-FMT) group and ameliorated testicular damage. Furthermore, treatment with RR-CO increased the fecal butyric acid level, serum Glucagon-like peptide-1 (GLP-1) level, and testicular GLP-1 receptor (GLP-1R) expression compared to those in DM mice. Finally, intraperitoneal administration of sodium butyrate (SB) significantly improved the pathological damage to the testis and reduced inflammation in the DM group. These data demonstrated a protective effect of RR-CO on DM-induced testicular damage by modulation of GM, which may be mediated by the butyric acid/GLP/GLP-1R pathway.

Ellagic acid inhibits proinflammatory intermediary manufacture by suppressing NF-κB/Akt, VEGF and activating Nrf-2/Caspase-3 signaling pathways in rat testicular damage: a new way for testicular damage cure and in silico approach

Ellagic acid (EA) has protective effect on testicular damage and this natural compound decreases oxidative damage. The present study aims to examine the preventive effect of ellagic acid (EA) against carbon tetrachloride (CCl₄)-induced testicular tissue damage in rats. In testicular tissue, tumor necrosis factor-α (TNF-α), Nuclear factor erythroid-2 related factor 2 (Nrf-2), B-cell lymphoma-2 (Bcl-2), vascular endothelial growth factor (VEGF), Nuclear factor-kappa B (NF-κB), cysteine aspartic proteases (caspase-3) and protein kinase B (Akt) synthesis levels were analyzed by western blot method, reactive oxygen species (ROS) was measured by malondialdehyde (MDA) levels, Glutathione (GSH) level and catalase (CAT) by spectrophotometer. As a result, in comparison with the CCl₄ group, caspase-3 and Nrf-2 protein synthesis levels increased in EA + CCl₄ group, however, VEGF, Bcl-2, NF-κB, TNF-α and Akt protein synthesis levels decreased, EA application raised GSH levels and CAT activity, reduced MDA levels. In this study, in silico tools were applied to confirm the activity of EA against the cancer with macromolecules such as the above mentioned transcription factors. EA, turned out to show significant activity similarly to some cocrystal ligands, particularly against cancer. These results points out that EA can be used as a testicular damage cure drug in future.

Ameliorative effects of Anchomanes difformis aqueous extract against oxidative stress in the testes and epididymis of streptozotocin-induced diabetic male Wistar rats

Hyperglycemia is a central trait of diabetes mellitus (DM) and is linked to an increase in free radical generation and oxidative stress in the testes, resulting in testicular tissue damage and male infertility. Synthetic medicines are commonly used to manage diabetes; however, they are costly and associated with adverse effects. As a result, the search for a safer and affordable alternative from medicinal plants that contain antioxidants has become imperative to scavenge free radicals caused by hyperglycaemia, thereby alleviating male reproductive dysfunction. Therefore, the present aimed to investigate the ameliorative effects of Anchomanes difformis aqueous extract against oxidative stress in the testes and epididymis of streptozotocin-induced diabetic male Wistar rats. A total of 64 male Wistar rats (eight weeks old) weighing 180 ± 10 mg/kg were divided into seven groups at random. Type 2 diabetic mellitus (T2DM) was induced by streptozotocin (STZ) and a 10% fructose injection intraperitoneally using 40 mg/kg body weight rats. The levels of malondialdehyde (MDA), catalase (CAT), and superoxide dismutase (SOD) activity, reduced glutathione (GSH) concentration, and ferric reducing antioxidant (FRAP) as well as 2, 2-diphenyl-1-picrylhydrazyl (DPPH) values were used to establish the testicular oxidative status. It was found that A. difformis extract significantly (p < 0.05) lowered MDA levels in diabetic rats. Both CAT and SOD activity were significantly (p < 0.05) lower following induction of DM and increased (p < 0.05) after treating with A. difformis. The findings of this study show that A. difformis extract could be a promising source of lead compounds for the development of a therapeutic agent to treat male infertility caused by DM complications.

Physalis pubescens L. alleviates testicular disruptions associated with streptozotocin-induced diabetes in male Wistar rats, Rattus norvegicus

Testicular impairment is a serious complication of diabetes that is mediated by oxidative stress and inflammation. Physalis has antioxidative and anti-inflammatory actions. Thus, the present study investigated the ameliorative role of Physalis juice (PJ) prepared from the fruits against testicular damages in streptozotocin (STZ)-induced diabetic rats. Adult male Wistar rats were divided randomly into five groups (n=6): control, orally administered 5 mL PJ/kg daily (PJ), injected intraperitoneally with a single dose of 55 mg STZ/kg without treatment (STZ), or treated daily with PJ (STZ+PJ) or with 500 mg metformin/kg (STZ+Met), for 28 days. The STZ group showed a marked elevation in the blood glucose level by 230%, whereas remarkable declines in the serum levels of testosterone (44%), follicle-stimulating hormone (FSH) (48%), and luteinizing hormone (LH) (36%), as compared to controls. In comparison to controls, the testis of the STZ group showed remarkable declines in the testis weight (15%), the glutathione (GSH) content (45%), mRNA and protein levels of B-cell lymphoma-2 (Bcl-2) (48 and 35%), mRNA and activities of superoxide dismutase (SOD) (63 and 40%), catalase (CAT) (56 and 31%), glutathione peroxidase (GPx) (51 and 44%), and glutathione reductase (GR) (62 and 43%), whereas marked elevations in the levels of interleukin-1 beta (IL-1β (169%), tumor necrosis factor-alfa (TNFα) (85%), nitric oxide (NO) (96%), malondialdehyde (MDA) (83%), mRNA and protein levels of Bcl-2-associated X protein (Bax) (400 and 61%), and mRNA level of caspase-3 (Cas-3) (370%). Some histopathological alterations were observed in the testicular tissue of the STZ group. In contrast, PJ markedly alleviated all the abovementioned disturbances. In conclusion, PJ at a dose of 5 mL/kg attenuated the diabetes-associated testicular impairments, which may be due to its antioxidative, anti-inflammatory, and antiapoptotic actions.

Type 2 diabetes mellitus and the risk of abnormal spermatozoa: A Mendelian randomization study

Abnormal spermatozoa can not only reduce the fertilization rate, but also prolong the natural conception time and even increase the risk of spontaneous miscarriage. Diabetes mellitus (DM) has become a major global health problem, and its incidence continues to rise, while affecting an increasing number of men in their reproductive years. Type 2 Diabetes Mellitus (T2DM), accounting for about 85-95% of DM, is closely related to the development of sperm. However, the exact association between T2DM and abnormal spermatozoa remains unclear. Herein, we designed a Two-sample Mendelian randomization (MR) study to explore the causal association between T2DM and abnormal spermatozoa risk in European population data which come from the GWAS summary datasets. We selected 9 single nucleotide polymorphisms (SNPs) of T2DM (exposure data) as instrumental variables (IVs), and then retrieved the suitable abnormal spermatozoa genome-wide association study (GWAS) data of European from Ieu Open GWAS Project database which includes 915 cases and 209,006 control as the outcome data. Our results indicate that strict T2DM might not result in a higher risk of abnormal spermatozoa genetically in Europeans (OR: 1.017, 95% confidence interval (CI): 0.771-1.342, p=0.902). Our findings demonstrate that only T2DM may not explain the relatively higher risk of abnormal spermatozoa in men with it in Europeans. In subsequent studies, more comprehensive and larger samples need to be studied to reveal the relationship and potential mechanism between T2DM and abnormal spermatozoa.

Impact of Quercus infectoria Galls Extract on Thyroid Gland and Testicular Functions in Diabetic Rats

Diabetes mellitus has been reported to be accompanied by thyroid and testicular dysfunctions. The objective of this study was to investigate the effect of Quercus infectoria galls (QIg) extract on the thyroid gland and testicular functions in diabetic rats. Sixteen rats were randomly divided into four equal groups, consisting of normal control, diabetic untreated control, diabetic treated with oral administration of 500 mg/kg BW and 1000 mg/kg BW, respectively for 15 days. Serum blood glucose, thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), testosterone (T), and luteinizing hormone (LH) were assessed. At the end of the experimental period, the rats were euthanized for histopathological analysis of thyroid gland and testis. Furthermore, immunohistochemistry was used to assess the expression of thyroid transcription factor-1 (TTF-1) in the thyroid gland of rats. The significant increase in serum blood glucose level in diabetic rats (DC) was markedly decreased by treatment with QIg extract (500 mg and 100 mg/kg BW) almost to the normal level. The reduced thyroid hormones, both the T3 and T4 were significantly recovered after 15 days of treatment with QIg extract (500 mg and 100 mg/kg BW). Whereas serum concentration of testosterone was significantly reduced in diabetic rats with QIg extract (500 mg and 100 mg/kg BW) treatment. Histopathological analysis of diabetic rats showed a wide range of morphological alterations in thyroid gland and testicular structures, which were almost completely, restored back to normal by treatment of rats with QIg extract. Furthermore, results showed overexpression of TTF-1 in the thyroid gland of diabetic rats, which was recovered back to normal expression after 15 days of treatment with QIg extract. These findings may provide new insights into the potential role of QIg extract as a promising therapeutic agent against diabetic complications in thyroid gland and testicular functions.

The effect of etanercept and anakinra on experimental type 2 diabetes pathology in rats

In this study, the effects of etanercept, anakinra, and their combination on streptozotocin-induced type 2 diabetes in rats were pathologically evaluated. A total of 30 rats were separated into 5 groups as control (C), diabetes (D), diabetes + anakinra (DA), diabetes + etanercept (DE), and diabetes + anakinra + etanercept (DAE). Anakinra (10 mg/kg/day, s.c.) and etanercept (10 mg/kg, twice weekly, s.c.) were administered to the DA and DE groups, respectively, and the DAE group received both anakinra and etanercept for 21 days. Histopathologically, pathological changes related to diabetes in internal organs occurred in the diabetes group, and there was a significant decrease (improvement) in these changes in the treatment groups (P < 0.05). There was no significant difference (P > 0.05) between the treatment groups, but some changes in the liver and kidneys were higher in the combined group which should be taken into account for longer use. Although there was no significant difference, etanercept was more effective on pancreatic lesion scores and anakinra was more effective on testicular changes. As a result, the single or combined use of IL-1 and TNF-α antagonists anakinra and etanercept were effective in the treatment of type 2 diabetes in rats without any toxic-pathological effect.

Highly active antiretroviral therapy conjugated silver nanoparticle ameliorates testicular injury in type-2 diabetic rats

Despite advances in managing human immunodeficiency virus (HIV) infection and success in the treatment prognosis using highly active antiretroviral therapy (HAART). The clinical efficacy of this regimen has been associated with increased adverse effects such as metabolic derangements and reproductive dysfunctions. These adverse effects necessitate a nanoparticle delivery vehicle like silver nanoparticles (AgNPs), a multi-functional drug delivery system, to transport the HAART to the viral reservoir site like testis. This study was therefore designed to evaluate the effects of HAART loaded AgNPs (HAART-AgNPs) on testicular oxidative stress markers, an inflammatory biomarker, and histomorphology in a rat model of diabetes. Thirty-six adult male Sprague-Dawley rats were randomly divided into two groups (n = 18) non-diabetic and fructose-streptozotocin (Frt-STZ) induced type 2 diabetes (T2DM). Thereafter, both groups were subdivided into three (n = 6) and treated with distilled water, HAART and HAART-AgNPs. HAART-AgNPs caused a significant increase (p < 0.05) in catalase (23.43 ± 0.92) level vs diabetic control (16.95 ± 1.04). Also, HAART-AgNP caused a significant reduction (p < 0.05) in malondialdehyde, interleukin-6 and blood glucose levels (1.94 ± 0.06, 93.65 ± 3.6, 287.33 ± 22.85 respectively), compared to their respective diabetic control values (2.18 ± 0.12, 143.4 ± 9.2, 372.16 ± 23.16). Furthermore, HAART-AgNPs mitigated tubular atrophy, basement membrane thickening, interstitial distension, fibrous elemental distortion and peri-interstitial tissue alterations in the testis of diabetic rats. The results from this study showed that administration of HAART-AgNPs to diabetic rats reduced testicular inflammation, improved glycaemic control, antioxidant status, and testicular histology. Therefore, conjugation of AgNP with HAART may cater for the reproductive dysfunction during the management of HIV infection.

MicroRNA 1228 Mediates the Viability of High Glucose-Cultured Renal Tubule Cells through Targeting Thrombospondin 2 and PI3K/AKT Signaling Pathway

AIM

The present study aimed to elucidate the potential function of microRNA 1228 (miR-1228) on the high glucose (HG)-damaged human renal proximal tubule cells (HK-2) and the underlying mechanism.

METHODS

The datasets GSE47185 and GSE51674 were downloaded from the Gene Expression Omnibus database for mining differently expressed mRNAs and miRNAs, respectively. Bioinformatics online tools were applied to predict the binding sites between miR-1228 and thrombospondin 2 (THBS2), which was confirmed by dual-luciferase assay. Real-time quantitative polymerase chain reaction was used to detect the mRNA level of miR-1228/THBS2. Western blot was used to detect the protein level of THBS2 and the PI3K/AKT signaling pathway-associated markers. HK-2 cells were cultured in HG (30 mM) to mimic hyperglycemia. Cell counting kit 8 and flow cytometry assays were utilized to determine the cell proliferation and apoptosis.

RESULTS

The expression of THBS2 was significantly upregulated in diabetic nephropathy (DN) based on bioinformatics tools and identified as a direct target of miR-1228. miR-1228 was downregulated in DN and HG-damaged HK-2 cells. HG notably reduced HK-2 cell proliferation. This negative effect was attenuated by transfecting with an miR-1228 mimic and aggravated by transfecting with an miR-1228 inhibitor. However, under basal condition, there was no significant effect on the HK-2 cell proliferation among blank control, mimic, and inhibitor groups. Overexpression of THBS2 abolished the elevating effect of the miR-1228 mimic on the HG-damaged HK-2 cell proliferation, while restored the inhibitory effects of the miR-1228 mimic on the cell apoptosis. On the contrary, the suppressive effects on the proliferation and the enhancive effects on the apoptosis by silencing miR-1228 in HK-2 cells stimulated with HG can be weakened by recommendation of THBS2 small interference RNAs. Furthermore, we also found that HG significantly enhanced the phosphorylation levels of PI3K and AKT. In terms of overexpression and knockdown experiments, Western blot analysis further revealed that miR-1228 inhibited the activation of the PI3K/AKT signaling pathway in HG-damaged HK-2 cells by regulating THBS2.

CONCLUSION

The findings illustrated that miR-1228 improved survivability and inhibited apoptosis in HK-2 cells stimulated with HG partly by restraining the activation of the PI3K/AKT signaling pathway.

Bacterial Infections Affect Male Fertility: A Focus on the Oxidative Stress-Autophagy Axis

Numerous factors trigger male infertility, including lifestyle, the environment, health, medical resources and pathogenic microorganism infections. Bacterial infections of the male reproductive system can cause various reproductive diseases. Several male reproductive organs, such as the testicles, have unique immune functions that protect the germ cells from damage. In the reproductive system, immune cells can recognize the pathogen-associated molecular patterns carried by pathogenic microorganisms and activate the host's innate immune response. Furthermore, bacterial infections can lead to oxidative stress through multiple signaling pathways. Many studies have revealed that oxidative stress serves dual functions: moderate oxidative stress can help clear the invaders and maintain sperm motility, but excessive oxidative stress will induce host damage. Additionally, oxidative stress is always accompanied by autophagy which can also help maintain host homeostasis. Male reproductive system homeostasis disequilibrium can cause inflammation of the genitourinary system, influence spermatogenesis, and even lead to infertility. Here, we focus on the effect of oxidative stress and autophagy on bacterial infection in the male reproductive system, and we also explore the crosslink between oxidative stress and autophagy during this process.

Repression of HDAC5 by acetate restores hypothalamic-pituitary-ovarian function in type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM) accounts for 90-95 % of worldwide diabetes cases and is primarily characterized by insulin resistance. Its progression as a chronic metabolic disease has been largely associated with female reproductive abnormalities, including ovarian dysfunction with consequent infertility. Epigenetic modifications have been suggested as a possible link to metabolic comorbidities. We therefore hypothesized that short chain fatty acids, acetate (ACA), a potential histone deacetylase inhibitor (HDAC) ameliorates hypothalamic-pituitary-ovarian (HPO) dysfunction in T2DM. Female Wistar rats weighing 160-190 g were allotted into three groups (n = 6/group): Control (vehicle; po), T2D and T2D + ACA (200 mg/kg; po). T2DM was induced by fructose administration (10 %; w/v) for 6 weeks and single dose of streptozotocin (35 mg/kg; ip). The present data showed that in addition to insulin resistance, increased fasting blood glucose and insulin, T2DM induced elevated plasma, hypothalamic and ovarian triglyceride, lipid peroxidation, TNF-α and glutathione depletion. Aside, T2DM also led to increased plasma lactate production and γ-Glutamyl transferase as well as decreased gonadotropins/17β-estradiol. Histologically, hypothalamus, pituitary and ovaries revealed disrupted neuronal cells/moderate hemorrhage, altered morphology/vascular congestions, and degenerated antral follicle/graafian follicle with mild fibrosis and infiltrated inflammatory cells respectively in T2D animals. Interestingly, these alterations were accompanied by elevated plasma/hypothalamic HDAC5 and attenuated when treated with acetate. The present results demonstrate that T2DM induces HPO dysfunction, which is accompanied by elevated circulating/hypothalamic HDAC5. The results in addition suggest that acetate restores HPO function in T2DM by suppression of HDAC5 and enhancement of insulin sensitivity.

Evaluation of testicular glycogen storage, FGF21 and LDH expression and physiological parameters of sperm in hyperglycemic rats treated with hydroalcoholic extract of Securigera Securidaca seeds, and Glibenclamide

Structural and physiological changes in sperm and semen parameters reduce fertility in diabetic patients. Securigera Securidaca (S. Securidaca) seed is a herbal medicine with hypoglycemic, antioxidant, and anti-hypertensive effects. The question now is whether this herbal medicine improves fertility in diabetic males. The study aimed to evaluate the effects of hydroalcoholic extract of S. Securidaca seeds (HESS), glibenclamide and a combination of both on fertility in hyperglycemic rats by comparing histological and some biochemical changes in testicular tissue and sperm parameters. The treatment protocol included administration of three doses of HESS and one dose of glibenclamide, as well as treatment with both in diabetic Wistar diabetic rats and comparison of the results with untrated groups. The quality of the testicular tissue as well as histometric parameters and spermatogenesis indices were evaluated during histopathological examination. Epididymal sperm analysis including sperm motility, viability, abnormalities, maturity, and chromatin structure were studied. The effect of HESS on the expression of LDH and FGF21 genes and tissue levels of glycogen, lactate, and total antioxidant capacity in testicular tissue was investigated and compared with glibenclamide. HESS improved sperm parameters in diabetic rats but showed little restorative effect on damaged testicular tissue. In this regard, glibenclamide was more effective than the highest dose of HESS and its combination with HESS enhanced its effectiveness so that histological tissue characteristics and sperm parameters were were comparable to those of healthy rats. The expression level of testicular FGF21 gene increased in diabetic rats, which intensified after treatment with HESS as well as glibenclamide. The combination of HESS and glibenclamide restored the expression level of testicular LDH gene, as well as tissue storage of glycogen, lactate and LDH activity, and serum testosterone to the levels near healthy control. S. Securidaca seeds can be considered as an effective supplement in combination with hypoglycemic drugs to prevent infertility complications in diabetes.

Effects of hypothermia and pentoxifylline on the adnexal torsion/detorsion injuries in a rat testis model

This study was designed to investigate the effects of separate and combined administration of hypothermia and pentoxifylline to preserve the effects on the testicles in an experimental model of testicular torsion/ detorsion injuries in rats. Forty male adult Wistar rats were randomly divided into five groups, control, torsion/detorsion (TD), torsion/detorsion/hypothermia (TD+ICE), torsion/detorsion received of pentoxifylline (40mg/kg, ip) (TD+PTX) and torsion/detorsion/hypothermia/PTX (TD+ICE+PTX). Left testicular torsion (TT) was performed for 4 and half hours, and ice fragments have been used at the beginning of torsion. After the reperfusion period (a week), oxidative maker's serum levels, testosterone hormone, sperm parameters, and histopathological and gene expression evaluations have been performed. Significant adverse changes were observed in the TD group for histological variables, sperm count, oxidative marker, testosterone hormone, Bax, BCL2 and caspase-3 expression. The parameters studied in the group receiving PTX improved in comparison with the TD group, while macroscopical parameters of both the hypothermia and PTX+ICE groups were not different compared with the TD group. The results revealed that PTX, as an antioxidant component, was protective against testicular torsion, while hypothermia and hypothermia plus PTX did not exhibit this property, which may have been due to the duration of hypothermia (4 hr) or reperfusion period.

The therapeutic role of lactobacillus and montelukast in combination with metformin in diabetes mellitus complications through modulation of gut microbiota and suppression of oxidative stress

Male reproductive dysfunction is one of the overlooked findings of diabetes mellitus (DM) that deserves greater scientific attention. This study is designed to explore the therapeutic potential of metformin and montelukast, in combination with Lactobacillus, for modulation of intestinal flora and suppression of oxidative stress in testicular and liver damage in diabetic male rats. A DM model was induced by streptozotocin (STZ)which caused functional, biochemical, and inflammatory injuries to the testicular and liver tissues. The experimental panel included nine rat groups: normal control, normal control plus metformin, normal control plus montelukast, DM control, DM plus montelukast, DM plus a combination of metformin and Lactobacillus, DM plus a combination of montelukast and Lactobacillus, and DM plus a combination of metformin and montelukast. In parallel, clinical evaluation of microscopic examination scoring, and hepatic and testicular injuries, were evaluated. Biochemical markers including glucose level, lipid profile, inflammatory markers (tumor necrosis factor- (TNF-α) and interleukin-17 (IL-17), Caspase-3, and Bax proteins expressions were measured. The change in the microbiota abundance was investigated using conventional and real-time PCR. The current study revealed a significant difference in the relative abundance of microbiota, where DM is associated with an enormous increase of Bacteroides spp., Clostridium spp., E. coli, and Fusobacterium spp., and a significant decrease in Bifidobacteria spp., and Lactobacillus spp., in contrast with normal control. Metformin and montelukast, in combination with Lactobacillus, significantly reversed the testicular and liver damage caused by STZ. Moreover, the drugs significantly reduced the oxidative, inflammatory, and apoptotic activities induced by STZ.

Identification of Novel Biomarker for Early Detection of Diabetic Nephropathy

Diabetic nephropathy (DN) is one of the most common complications of diabetes mellitus. After development of DN, patients will progress to end-stage renal disease, which is associated with high morbidity and mortality. Here, we developed early-stage diagnostic biomarkers to detect DN as a strategy for DN intervention. For the DN model, Zucker diabetic fatty rats were used for DN phenotyping. The results revealed that DN rats showed significantly increased blood glucose, blood urea nitrogen (BUN), and serum creatinine levels, accompanied by severe kidney injury, fibrosis and microstructural changes. In addition, DN rats showed significantly increased urinary excretion of kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL). Transcriptome analysis revealed that new DN biomarkers, such as complementary component 4b (C4b), complementary factor D (CFD), C-X-C motif chemokine receptor 6 (CXCR6), and leukemia inhibitory factor (LIF) were identified. Furthermore, they were found in the urine of patients with DN. Since these biomarkers were detected in the urine and kidney of DN rats and urine of diabetic patients, the selected markers could be used as early diagnosis biomarkers for chronic diabetic nephropathy.

Ellagic acid improved diabetes mellitus-induced testicular damage and sperm abnormalities by activation of Nrf2

Diabetes mellitus induces testicular damage, increases sperm abnormalities, and impairs reproductive dysfunction due to induction of endocrine disturbance and testicular oxidative stress. This study evaluated the reproductive protective effect of ellagic acid (EA) against testicular damage and abnormalities in sperm parameters in Streptozotocin (STZ)-induced diabetic rats (T1DM) and examined some possible mechanisms of protection. Adult male rats were segregated into 5 groups (n = 12 rat/each) as control, control + EA (50 mg/kg/day), T1DM, T1DM + EA, and T1DM + EA + brusatol (an Nrf-2 inhibitor) (2 mg/twice/week). All treatments were conducted for 12 weeks, daily. EA preserved the structure of the seminiferous tubules, prevented the reduction in sperm count, motility, and viability, reduced sperm abnormalities, and downregulated testicular levels of cleaved caspase-3 and Bax in diabetic rats. In the control and diabetic rats, EA significantly increased the circulatory levels of testosterone, reduced serum levels of FSH and LH, and upregulated Bcl-2 and all steroidogenic genes (StAr, 3β-HSD1, and 11β-HSD1). Besides, it reduced levels of ROS and MDA but increased levels of GSH and MnSOD and the transactivation of Nrf2. All these biochemical alterations induced by EA were associated with increased activity and nuclear accumulation of Nrf2. However, all these effects afforded by EA were weakened in the presence of brusatol. In conclusion, EA could be an effective therapy to alleviated DM-induced reproductive toxicity and dysfunction in rats by a potent antioxidant potential mediated by the upregulation of Nrf2.

Rescue effect of sodium acetate in diabetes mellitus-associated testicular dysfunction is accompanied by PCSK9 modulation

Diabetes mellitus (DM) is a global health burden, affecting about 463 million of the adult population worldwide. Approximately 94% of diabetic male individuals develop varying degrees of testicular disorders (TDs), which usually result in hypogonadism, hypotestosteronemia and defective spermatogenesis and steroidogenesis. Short chain fatty acids (SCFAs) have shown potential benefits in metabolic health. However, its effect on TD associated with DM is not clear. Howbeit, the present study investigated the hypothesis that SCFAs, acetate would ameliorate TD accompanying DM, possibly by suppressing proprotein convertase subtilisin/kexin type 9 (PCSK9). Male Wistar rats (210-240 g) were allotted into groups (n = 6/group): control (vehicle; po), DM with/without 200 mg/kg (po) of sodium acetate (SAc). Diabetes was induced by streptozotocin 65 mg/kg (iv) after a dose of nicotinamide (110 mg/kg). Semen/biochemical and histological analyses were performed with appropriate methods. In addition to hyperglycemia, hyperinsulinemia and reduced insulin sensitivity, DM led to increased serum and testicular triglyceride or total cholesterol/high-density lipoprotein cholesterol ratio, low-density lipoprotein cholesterol, malondialdehyde, TNF-α, IL-6 and PCSK9 as well as reduced high-density lipoprotein cholesterol and glutathione. Moreover, DM caused TD which is characterized by altered sperm parameters, disrupted tissue architecture, atrophied seminiferous tubules, deleterious spermatogonia, disappearance of lumen and cellular degeneration as well as decreased luteinizing hormone and testosterone. However, the administration of SAc attenuated these alterations. The study demonstrates that DM-induced TD is accompanied by elevated PCSK9. The results however suggest that SAc rescues testicular disorder/dysfunction associated with DM by suppression of PCSK9 and improvement of insulin sensitivity.

Momordica charantia Extract Protects against Diabetes-Related Spermatogenic Dysfunction in Male Rats: Molecular and Biochemical Study

More than 90% of diabetic patients suffer from sexual dysfunction, including diminished sperm count, sperm motility, and sperm viability, and low testosterone levels. The effects of Momordica charantia (MC) were studied by estimating the blood levels of insulin, glucose, glycosylated hemoglobin (HbA1c), testosterone (TST), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in diabetic rats treated with 250 and 500 mg/kg b.w. of the total extract. Testicular antioxidants, epididymal sperm characteristics, testicular histopathology, and lesion scoring were also investigated. Testicular mRNA expression of apoptosis-related markers such as antiapoptotic B-cell lymphoma-2 (Bcl-2) and proapoptotic Bcl-2-associated X protein (Bax) were evaluated by real-time PCR. Furthermore, caspase-3 protein expression was evaluated by immunohistochemistry. MC administration resulted in a significant reduction in blood glucose and HbA1c and marked elevation of serum levels of insulin, TST, and gonadotropins in diabetic rats. It induced a significant recovery of testicular antioxidant enzymes, improved histopathological changes of the testes, and decreased spermatogenic and Sertoli cell apoptosis. MC effectively inhibited testicular apoptosis, as evidenced by upregulation of Bcl-2 and downregulation of Bax and caspase-3. Moreover, reduction in apoptotic potential in MC-treated groups was confirmed by reduction in the Bax/Bcl-2 mRNA expression ratio.

Diabetes mellitus and the impairment of male reproductive function: Possible signaling pathways

BACKGROUND AND AIMS

Today, it has been shown that diabetes mellitus (DM) can affect male fertility. Glucose metabolism is a vital process in spermatogenesis that is impacted by diabetes condition. But the mechanisms by which DM causes male infertility are not wholly clarified. The aim of this review is to provide brief information about the influence of hyperglycemia on male fertility and specific emphasis on the molecular signaling pathway that is involved.

METHODS

Broad literature search in the electronic database "Pubmed", "Google Scholar", the website of "World Health Organization" (WHO) and Control Disease and Prevention (CDC) took place. There was no time restriction. A key criterion for the selection of articles was English and language. Finally, one hundred thirty seven articles were included in the review.

RESULTS

Diabetes mellitus affects many signaling pathways that involved in the spermatogenesis. It seems that increased ROS and oxidative stress in the diabetes is the beginning of all fertility problems and affects all of involved signaling pathways in the spermatogenesis.

CONCLUSIONS

It seems that there was strong interconnected between oxidative stress and all of involved signaling pathways in the reproductive problems in diabetes. So, approaches that diminish oxidative stress in the testis can be effective in improving diabetes related infertility complications.

Metformin Ameliorates Diabetic Cardiomyopathy by Activating the PK2/PKR Pathway

Diabetic cardiomyopathy (DCM) is a complication of diabetes that can cause damage to myocardial structure and function. Metformin (Met) is a widely used type 2 diabetes treatment drug that exerts cardioprotective effects through multiple pathways. Prokineticin 2 (PK2) is a small-molecule secreted protein that plays pivotal parts in cardiomyocyte survival and angiogenesis. However, the role of Met in regulating the PK2 signaling pathway in DCM remains unclear. This experiment explored the effects of Met on high glucose (HG)-induced injury through the PK2/PKR pathway in vivo and in vitro. Cardiomyocytes isolated from adult or AKT-knockout mice were treated with HG (33 mmol/L) and PK2 or AKT1/2 kinase inhibitor (AKT inhibitor). Heart contraction properties based on cell shortening were evaluated; these properties included the resting cell length, peak shortening (PS), maximum speed of shortening/relengthening (±dL/dt), time to 90% relengthening (TR₉₀), and time to peak shortening (TPS). Mice with streptozotocin-induced diabetes were treated with Met to evaluate cardiac function, myocardial structure, and the PK2/PKR and AKT/GSK3β pathways. Moreover, H9c2 cardiomyocytes were exposed to HG in the absence or presence of Met with or without the PK2 antagonist PKRA7 or the AKT inhibitor, and apoptotic proteins such as Bax and Bcl-2 and the PK2/PKR and AKT/GSK3β pathways were evaluated using western blot analysis. The prolongation of TR₉₀ and decreases in PS and ±dL/dt caused by HG were ameliorated by PK2 in cardiomyocytes, but the effects of PK2 were ameliorated or negated by the AKT inhibitor and in AKT-knockout mice. Diabetic mice showed metabolic abnormalities, aberrant myocardial enzyme levels, declines in myocardial systolic and diastolic function associated with myocardial fibrosis, and pronounced apoptosis, but these effects were greatly rescued by Met treatment. Moreover, PK2, PKR1, and PKR2 expression and p-AKT/AKT and p-GSK3β/GSK3β ratios were decreased in diabetic mice, and these decreases were attenuated by Met. Likewise, H9c2 cells exposed to HG showed reduced PK2/PKR expression and decreased p-AKT/AKT and p-GSK3β/GSK3β ratios, and these effects were nullified by Met. In addition, the effects of Met on cardiomyocytes exposed to HG were abolished after intervention with PKRA7 or the AKT inhibitor. These results suggest that Met can activate the PK2/PKR-mediated AKT/GSK3β pathway, thus improving cardiac function and alleviating apoptosis in DM mice.

Kidney-targeted baicalin-lysozyme conjugate ameliorates renal fibrosis in rats with diabetic nephropathy induced by streptozotocin

BACKGROUND

Diabetic nephropathy (DN) is one of the most common and serious complications of diabetes, and is the most important cause of death for diabetic patients. Baicalin (BAI) has anti-oxidative, anti-inflammatory and anti-apoptotic activities, which play a role in attenuating insulin resistance and protecting the kidney. Moreover, cell-specific targeting of renal tubular cells is an approach to enhance drug accumulation in the kidney.

METHODS

Forty-five Sprague-Dawley rats were divided into four groups. A diabetes model was created using streptozotocin (STZ) intraperitoneally injection. The four groups included: Control group (n = 10), DN (n = 15), BAI treatment (BAI; n = 10) and BAI-LZM treatment (BAI-LZM; n = 10) groups. In the current study, the renoprotection and anti-fibrotic effects of BAI-lysozyme (LZM) conjugate were further investigated in rats with DN induced by STZ compared with BAI treatment alone.

RESULTS

The results suggest that BAI-LZM better ameliorates renal impairment, metabolic disorder and renal fibrosis than BAI alone in rats with DN, and the potential regulatory mechanism likely involves inhibiting inflammation via the nuclear factor-κB signaling pathway, inhibiting extracellular matrix accumulation via the transforming growth factor-β/Smad3 pathway and regulating cell proliferation via the insulin-like growth factor (IGF)-1/IGF-1 receptor/p38 Mitogen-activated protein kinase (MAPK) pathway. BAI and the kidney-targeted BAI-LZM can utilize the body's cytoprotective pathways to reactivate autophagy (as indicated by the autophagy markers mechanistic target of rapamycin and sirtuin 1 to ameliorate DN outcomes.

CONCLUSIONS

Our data support the traditional use of S. baicalensis as an important anti-DN traditional chinese medicine (TCM), and BAI, above all BAI-LZM, is a promising source for the identification of molecules with anti-DN effects.

Longitudinal Average Glucose Levels and Variance and Risk of Stroke: A Chinese Cohort Study

BACKGROUND

Diabetes is a known independent risk factor for stroke. However, whether higher glucose levels (126-139.9 mg/dl) can increase the risk of stroke in people without diabetes is still unknown. Moreover, as a fluctuating parameter, long-term glucose levels may also be related to the risk of stroke outcome. It is important to explore the correlation between long-term average blood glucose, as well as its variability, and stroke.

METHODS

We used 40,975 clinical measurements of glucose levels and 367 measurements of glycated hemoglobin A1c levels from 12,321 participants without stroke to examine the relationship between glucose levels and the risk of stroke. Participants were from the Weitang Geriatric Diseases study, including 5,707 men and 6,614 women whose mean age at baseline was 60.8 years; 1,011 participants had diabetes, and 11,310 did not. We estimated the long-term average blood glucose level based on the multilevel Bayesian model and fit in Cox regression models, stratified according to diabetes status.

RESULTS

Over a median follow-up period of 5 years, stroke developed in 279 of the 12,321 participants (244 without diabetes and 35 with). For people with an average glucose level of 126-139.9 mg per deciliter, compared with 90-99.9 mg per deciliter, the adjusted hazard ratio (HR) for total stroke was 1.78 (95% confidence interval (CI), 1.16-2.75), and the HR for levels higher than 140 mg per deciliter was 1.89 (95% CI, 1.09-3.29). Among those without diabetes whose glucose level was higher than 140 mg per deciliter, compared with 90-99.9 mg per deciliter, the adjusted HRs for total stroke and fatal stroke were 3.66 (95% CI, 1.47-9.08) and 5 (95% CI, 1.77-14.15), respectively. For a glucose standard deviation level higher than 13.83 mg per deciliter, compared with that lower than 5.91 mg per deciliter, the adjusted HR for total stroke was 2.31 (95% CI, 1.19-4.48).

CONCLUSIONS

Our results suggest that higher average glucose levels (126-139.9 mg/dl) and variance may be risk factors for stroke, even among people without diabetes diagnosis.