Vitamin CNa enhances the antioxidant ability of chicken myocardium cells and induces heat shock proteins to relieve heat stress injury.

In order to explore the function of vitamin C (VC) and VC-Na in the relief of heat stress injury in chicken cardiomyocytes, 150 30-day-old specific-pathogen-free chickens were randomly divided into a control group (fed normal drinking water), a VC group (50 µg/mL VC in drinking water), and a VC-Na group (50 µg/mL VC-Na in drinking water). After 7 days of adaptation feeding, the chickens were subjected to heat stress at 40 ± 2 °C and 60%-70% humidity for 0, 1, 3, 5, and 10 h, respectively, and the sera and heart tissues of the chickens were collected immediately at the corresponding heat stress time points. The effects of VC and VC-Na supplementation on the relief of chicken myocardial cell injury following heat stress was studied by detecting the levels of LDH, CK, CK-MB, and total antioxidant capacity (T-AOC) in the sera, and through histopathological analysis and the expression of CRYAB, Hsp27, and Hsp70 in the myocardial cells. The results showed that supplementing with 50 µg/mL VC or VC-Na significantly reduced the levels of LDH, and CK-MB in serum as well as heat-stress-induced granular and vacuolar degeneration, myocardial fiber breakage, and cell necrosis, indicating effective resistance to heat-stress damage. Additionally, the levels of T-AOC in serum were increased in the VC and VC-Na groups, suggesting enhancing of antioxidant capacity. Furthermore, the expression of CRYAB were induced at 0, 3, 5, and 10 h (P < 0.01) in both VC and VC-Na group, and that of Hsp70 were induced at 0 h (P < 0.05) in VC group and at 0, 3, 5, 10 h (P < 0.01) in VC-Na group. Thus, supplementing chicken diets with VC or VC-Na presented heat-stress damage resistance by enhancing antioxidant capacity and inducing expression of CRYAB and Hsp70.

Targeting estrogen receptors in colorectal cancer.

Hormones have become a useful therapeutic aspect of clinical endocrinology but how to use them to optimize the health benefits and avoid adverse effects is a major challenge. Estrogen is an indispensable hormone for proper biological functioning but is also implicated with the pathology of both the reproductive and non-reproductive tissues. Abnormal estrogen receptor signaling may increase the risk of development of a variety of diseases including colorectal cancer (CRC). Estrogen receptor beta (ERß) is the predominant subtype in the colonic epithelium and confers the anti-tumor effect through various mechanisms. Many investigators have embarked on the search for the biological mechanisms by which estrogen and estrogen-like compounds may influence the pathogenesis of CRC. This review explores the recent findings on the therapeutic role of ERß in the colonic epithelium as a prospective candidate for targeted endocrine therapy in CRC.

Rosemary Reduces Heat Stress by Inducing CRYAB and HSP70 Expression in Broiler Chickens.

Heat stress negatively affects poultry production and animal health. In response, animals invoke a heat stress response by inducing heat shock proteins (HSPs). Scientists are actively seeking natural products that can enhance the heat shock response. The present study aimed at assessing the effects of a purified rosemary extract comprising antioxidant compounds on the heat shock response and HSP expression profile in broiler chickens. The response of broilers to HS in the presence of purified rosemary extract was assessed using an in vivo myocardial cell model. Pathological lesions of heart tissue were examined microscopically. The levels and activities of enzymes associated with heart damage and oxidative damage were detected. Immunohistochemical staining was performed for HSPs in myocardial cells. The results showed that lactate dehydrogenase (LDH), creatine kinase (CK), and myocardial CK (CKMB) levels were reduced by the purified rosemary extract before and during heat stress. Heat stress alone increased CK and CKMB levels. The levels of oxidative damage-associated enzymes were compared between the rosemary + heat stress and heat stress-alone groups. The results indicated that in terms of these enzymes, the purified rosemary extract induced a more antioxidative state. Pathological examinations showed that heat stress caused myocardial fiber fracture, karyopyknosis, and degeneration. The addition of purified rosemary extract ameliorated these lesions to some degree, preserving more of the basic structure. Heat stress decreased the cellular levels of crystallin alpha B (CRYAB) and HSP70. The addition of the purified rosemary extract significantly increased the levels of CRYAB and HSP70 during heat stress (p < 0.0001). Immunohistochemistry showed that after rosemary treatment, CRYAB and HSP70 showed more intense staining compared with the no heat stress control group. In the rosemary + heat group, after 10 hours of heat stress, the staining intensity of these two proteins remained higher than in the heat stress group. Thus, purified rosemary extract could induce high levels of HSP70 and CRYAB in chicken hearts before and during heat stress. Purified rosemary extract could be used to alleviate heat stress in broiler chickens.

Aspirin-induced heat stress resistance in chicken myocardial cells can be suppressed by BAPTA-AM in vitro.

Our recent studies have displayed the protective functions of aspirin against heat stress (HS) in chicken myocardial cells, and it may be associated with heat shock proteins (HSPs). In this study, we further investigated the potential role of HSPs in the aspirin-induced heat stress resistance. Four of the most important HSPs including HspB1 (Hsp27), Hsp60, Hsp70, and Hsp90 were induced by aspirin pretreatment and were suppressed by BAPTA-AM. When HSPs were induced by aspirin, much slighter HS injury was detected. But more serious damages were observed when HSPs were suppressed by BAPTA-AM than those cells exposed to HS without BAPTA-AM, even the myocardial cells have been treated with aspirin in prior. Comparing to other HSPs, HspB1 presented the largest increase after aspirin treatments, 86-fold higher than the baseline (the level before HS). These findings suggested that multiple HSPs participated in aspirin's anti-heat stress function but HspB1 may contribute the most. Interestingly, during the experiments, we also found that apoptosis rate as well as the oxidative stress indicators (T-SOD and MDA) was not consistently responding to heat stress injury as expected. By selecting from a series of candidates, myocardial cell damage-related enzymes (CK-MB and LDH), cytopathological tests, and necrosis rate (measured by flow cytometry assays) are believed to be reliable indicators to evaluate heat stress injury in chicken's myocardial cells and they will be used in our further investigations.