Melatonin or vitamin C attenuates lead acetate-induced testicular oxidative and inflammatory damage in mice by inhibiting oxidative stress mediated NF-κB signaling

Diacylglycerol kinase alpha regulates post-hepatectomy liver regeneration

Diacylglycerol kinases (DGKs) phosphorylate diacylglycerol to generate phosphatidic acid, which plays important roles in intracellular signal transduction. DGKα is reportedly associated with progression of tumors, including hepatocellular carcinomas, but its relationship with liver regeneration has not been examined. The purpose of this research is to elucidate the role of DGKα in liver regeneration. Here, we provide a detailed examination of C57BL/6 wild-type and DGKα knockout (KO) mice subjected to 70% partial hepatectomy (70% PH) modeling, including survival rates, hematological marker and gene expression levels, and histological analyses of factors related to liver regeneration. Following 70% PH, DGKα KO mice produce higher levels of hepatobiliary enzymes and have a higher incidence of jaundice compared with wild-type mice, with a death rate of ~ 40%. Furthermore, they exhibit impaired glycogen and lipid consumption, low liver energy charge, and hepatocyte hypertrophy disorder, accompanied by significantly reduced liver expression of proliferating cell nuclear antigen and cyclin D. We conclude that DGKα is a key molecule in the post-PH liver regeneration process and may have potential as a therapeutic target for the acceleration of liver regeneration.

Adolescent exposure to organophosphate insecticide malathion induces spermatogenesis dysfunction in mice by activating the HIF-1/MAPK/PI3K pathway

Chemical-caused reproductive dysfunction has emerged as a global public health concern. This study investigated the adverse effects of the organophosphorus pesticide malathion on reproductive function in adolescent male mice at environmentally relevant concentrations. The results indicated that eight-week malathion exposure reduced testis weight, caused sex and thyroid hormone disorders, and induced testicular spermatogenic epithelium damage and oxidative stress. Testicular RNA sequencing indicated that malathion significantly affected testicular energy metabolism, hypoxia-inducible factor 1 (HIF-1) signaling, and steroid hormone biosynthesis pathways. Malathion significantly increased the gene and protein expression of HIF-1α by upregulating key genes in the mitogen-activated protein kinase (MAPK) pathway (Map2k2, Mapk3, and Eif4e2) and the phosphatidylinositol 3-kinase (PI3K) pathway (Pik3r2 and Akt1). Furthermore, malathion downregulated HIF-1α degradation-regulating genes while upregulating anaerobic metabolism and inflammation-related genes, thereby inhibiting normoxia and promoting hypoxia processes. Testicular hypoxia subsequently induced steroid hormone biosynthesis disorders and spermatogenesis dysfunction. Molecular docking verified that malathion interfered with HIF-1α and steroid hormone synthases (CYP11A1, CYP17A1 and CYP19A1) by forming hydrogen bonds and hydrophobic interactions with these proteins. This study presents the first evidence that malathion triggers spermatogenesis dysfunction in mice through activating the HIF-1/MAPK/PI3K pathway, providing a comprehensive understanding of the reproductive toxicity risks associated with organophosphorus pesticides.

Association Between Vitamin Intake and Colorectal Cancer: Evidence from NHANES Data

PURPOSE

This study aims to investigate the associations between vitamins and colorectal cancer (CRC) based on a national sample of US adults.

METHODS

A total of 6200 samples were collected from the National Health and Nutrition Examination Survey to explore the relationship between vitamins (specifically, A, C, and D) and CRC. Logistic regression models were employed to assess the associations between dietary vitamin intake and CRC.

RESULTS

Our findings indicate a negative association between vitamin C intake and CRC. However, the associations of vitamin A and vitamin D with CRC were not statistically significant. For vitamin C, compared to the first tertile, the odds ratios (ORs) and 95% confidence intervals (CIs) were 0.91 (0.76-0.97) for the second tertile and 0.81 (0.64-0.95) for the third tertile (P < 0.01). Conversely, for vitamin A, compared to the first tertile, the odds ratios (ORs) and 95% confidence intervals (CIs) were 1.02 (0.82-1.22) for the second tertile and 1.04 (0.75-1.25) for the third tertile (P < 0.01). For vitamin D, compared to the first tertile, the odds ratios (ORs) and 95% confidence intervals (CIs) were 0.96 (0.84-1.06) for the second tertile and 1.01 (0.83-1.15) for the third tertile (P < 0.01). Additionally, the negative association between vitamin C and CRC was more pronounced among females (0.76, 0.67-0.92), individuals aged 60 and above (0.75, 0.69-0.95), and those with a BMI > 30 (0.78, 0.67-0.93).

CONCLUSION

Our findings suggest that higher vitamin C intake is associated with a reduced prevalence of CRC. However, further large-scale prospective cohort studies are warranted to validate our results.

Rutin alleviates Pb-induced oxidative stress, inflammation and cell death via activating Nrf2/ARE system in SH-SY5Y cells

Lead (Pb) is harmful to almost all organs, particularly the developmental neural system, and previous studies revealed oxidative stress played an important role in Pb neurotoxicity. Rutin, a type of flavonoid glycoside found in various plants and fruits, is widely used as a dietary supplement due to its antioxidant and anti-inflammatory properties, but whether rutin could protect against Pb neurotoxicity is unclear. In this study, we found rutin treatment significantly alleviated Pb-induced cell death, oxidative stress, and inflammation, resulting in cell survival. Moreover, rutin treatment promoted nuclear factor erythroid 2-related factor 2 (Nrf2) translocation from cytoplasm to nucleus and subsequently activated antioxidant and detoxifying enzymes expression including HO-1. Knocking down Nrf2 by siRNA transfection abolished this protection of rutin against Pb. Overall, rutin could alleviate Pb-induced oxidative stress, inflammation, and cell death by activating the Nrf2/antioxidant response elements (ARE) system.

Impact of chronic sleep deprivation on male reproductive health: Insights from testicular and epididymal responses in mice

BACKGROUND

Sleep deprivation (SD) can cause damage to the male reproductive system. However, the duration required for such damage and the specific sequence and severity of damage to the testis and epididymis remain unclear.

OBJECTIVE

To investigate the effects of different durations of SD on different parts of the testis and epididymis caput, corpus, and cauda.

METHODS

Adult ICR mice were randomly assigned to five groups: the SD group (SD for 18 h/day for 1, 2, 3, or 4 weeks), the SD + Vit E group (supplemented with Vit E 50 mg/kg/d during 4 weeks of SD, the SD+NS group (saline supplementation during 4 weeks of SD), the SD + RS group (5 weeks of recovery sleep after 4 weeks of SD), and a normal sleep control (Ctrl) group. Following the interventions, sperm parameters, testicular and epididymal histopathology, inflammatory response, and oxidative stress markers were compared between the groups.

RESULTS

Compared to the Ctrl group, the SD group showed a decrease in sperm motility and concentration from SD 2 W and SD 3 W, respectively. Decreases in sperm concentration and motility were more pronounced in the cauda compared to the caput and corpus. Pathological damage was less severe in the epididymis caput than in the corpus and cauda. After 4 weeks of SD, inflammation and oxidative stress increased in both testes and epididymis. Both sleep recovery and vitamin E supplementation showed significant improvements, though they did not fully reach the level of the Ctrl group.

CONCLUSION

Chronic SD for more than 2 weeks causes varying degrees of damage to the testis, epididymis caput, corpus, and cauda in male mice. This damage is not fully reversible after 5 weeks of sleep recovery and antioxidant stress treatment. These findings help us to identify and prevent SD damage to the male reproduction at an early stage.

Nerve growth factor alleviates arsenic-induced testicular injury by enhancing the function of Sertoli cells

Sertoli cells (SCs) maintain testicular homeostasis and promote spermatogenesis by forming the blood-testis barrier (BTB) and secreting growth factors. The pro-proliferative and anti-apoptotic effects of nerve growth factor (NGF) on SCs have been proved previously. It is still unclear whether the damage effect of arsenic on testis is related to the inhibition of NGF expression, and whether NGF can mitigate arsenic-induced testicular damage by decreasing the damage of SCs induced by arsenic. Here, the lower expression of NGF in testes of arsenic exposed mice (freely drinking water containing 15 mg/l of NaAsO2) was observed through detection of Western blot and Real-time PCR. Subsequently, hematoxylin and eosin (HE) staining, Evans blue staining and transmission electron microscopy were used to evaluate the pathology, BTB permeability and tight junction integrity in testes of control mice, arsenic exposed mice (freely drinking water containing 15 mg/l of NaAsO2) and arsenic + NGF treated mice (freely drinking water containing 15 mg/l of NaAsO2 + intraperitoneal injection with 30 μg/kg of NGF), respectively. Evidently, spermatogenic tubule epithelial cells in testis of arsenic exposed mice were disordered and the number of cell layers was reduced, accompanied by increased permeability and damaged integrity of the tight junction in BTB, but these changes were less obvious in testes of mice treated with arsenic + NGF. In addition, the sperm count, motility and malformation rate of mice treated with arsenic + NGF were also improved. On the basis of the above experiments, the viability and apoptosis of primary cultured SCs treated with arsenic (10 μM NaAsO2) or arsenic + NGF (10 μM NaAsO2 + 100 ng/mL NGF) were detected by Cell counting kit-8 (CCK8) and transferase-mediated DUTP-biotin nick end labeling (TUNEL) staining, respectively. It is found that NGF ameliorated the decline of growth activity and the increase of apoptosis in arsenic-induced SCs. This remarkable biological effect that NGF inhibited the increase of Bax expression and the decrease of Bcl-2 expression in arsenic-induced SCs was also determined by western blot and Real-time PCR. Moreover, the decrease in transmembrane resistance (TEER) and the expression of tight junction proteins ZO-1 and occludin was mitigated in SCs induced by arsenic due to NGF treatment. In conclusion, the above results confirmed that NGF could ameliorate the injury effects of arsenic on testis, which might be related to the function of NGF to inhibit arsenic-induced SCs injury.

The single and mixed impacts of cadmium, cobalt, lead, and PAHs on systemic immunity inflammation index in male and female

Background

Studies on the association between mixed exposure to common pollutants such as cadmium (Cd), cobalt (Co), lead (Pb), and polycyclic aromatic hydrocarbons (PAHs) with Systemic Immune Inflammatory Index (SII), a novel hemocyte-based inflammatory marker, have not been reported. This study explored the relationship between co-exposure to Cd, Co, Pb, PAHs, and SII.

Methods

In this study, we used data from the National Health and Nutrition Examination Survey and enrolled adults with complete information on Cd, Co, Pb, PAHs, and SII. The linear regression was used to analyze the association of single pollutants with SII. Furthermore, a Bayesian Kernel Machine Regression analysis and a generalized weighted quantile sum regression analysis were used to analyze the association between mixed exposure to Cd, Co, Pb, and six PAHs and SII. We also separated males and females and analyzed the different effects of pollutants on SII, respectively.

Results

5,176 participants were included in the study. After adjusting for age, gender, race, education, smoking, drinking, physical activity, and sedentary, Cd, Co, 1-OHN, 2-OHN and 2-OHF were positive with SII in the total population. Compared with the 50th percentile, the joint effect of pollutants on SII was positive. In the total population, males, and females, the top contaminant with the highest effect weights on SII were Co, Cd, and 1-OHN, respectively. The result of interaction analysis showed that the low concentrations of Cd had an elevation effect on SII in males.

Conclusion

This study found a positive association of mixed exposure to Cd, Co, Pb, and six PAHs with SII, which occurred mainly in females.

Repairing Effect of Mesenchymal Stem Cells on Lead Acetate-Induced Testicular Injury in Mice

Lead acetate can cause testicular damage in males. In this study, we assessed the repairing effects of human umbilical cord mesenchymal stem cells (MSCs) on testicular injury caused by lead acetate in mice. MSCs were injected into mice with testicular injury by intraperitoneal injection, and the organ coefficient of reproductive organs, sperm motility, hormone level and antioxidant index of mice were tested. Compared with the normal group, the coefficient of reproductive organs and sperm motility were reduced in the model group, and histopathology showed obvious testicular injury, proving successful modeling. Compared with the model group, the reproductive organ coefficient and sperm motility were improved in the experimental group, and histopathology showed that the testicular injury could be significantly improved. Sex hormone secretion tends to be normal, and the antioxidant index increased. Sequencing results showed that there were 485 upregulated genes and 172 downregulated genes between the model group and the control group, and 210 upregulated genes and 482 downregulated genes between the experimental group and the model group. Differentially expressed genes are mainly concentrated in AMP-activated protein kinase (AMPK) signaling pathway, apoptosis signaling pathway, and arginine biosynthesis signaling pathway. Overall, MSCs can significantly improve the degree of damages to mice testis caused by lead acetate and have a certain repairing effect.