In this report, the protective effect and molecular mechanism of Chaihu Shugan San-containing serum on corticosterone(CORT)-induced mitochondrial damage in pheochromocytoma(PC12) cells was studied based on CORT-induced rat PC12 cell model. The cultured cells were divided into five groups: blank control group, CORT group(400 μmol·L~(-1) CORT), Chaihu Shugan San-containing serum group(400 μmol·L~(-1) CORT + 10% Chaihu Shugan San-containing serum), control serum group(400 μmol·L~(-1) CORT + 10% control serum), and fluoxetine group(400 μmol·L~(-1) CORT + 10% fluoxetine-containing serum). The study was carried out by cell activity detection, mitochondrial morphology observation, membrane potential measurement, energy metabolism analysis, and mitochondrial dynamics-related protein detection. The results showed that CORT treatment significantly reduced the survival rate of PC12 cells, altered mitochondrial morphology, and decreased mitochondrial membrane potential and adenosine triphosphate(ATP) synthetic rate. Both Chaihu Shugan San-and fluoxetine-containing serum significantly increased the survival rate of CORT-treated PC12 cells and the ATP synthetic rate in the mitochondria. Unlike fluoxetine, Chaihu Shugan San-containing serum significantly inhibited the decrease in mitochondrial membrane potential caused by CORT and increased the oxygen consumption rate(OCR) values of both mitochondrial maximum respiration and reserve respiration capacity. Western blot analysis showed that CORT induced upregulated protein expressions of dynamin-related protein 1(Drp1) and peroxisome proliferator-activated receptor gamma co-activator 1α(PGC-1α) in PC12 cells and specific protein expression of optic atrophy protein 1(OPA1), yet it repressed the protein expressions of silent information regulator 1(SIRT1) and mitochondrial fusion protein 1(Mfn1) in PC12 cells. Both Chaihu Shugan San-and fluoxetine-containing serum significantly inhibited the protein expression of Drp1. However, only Chaihu Shugan San-containing serum could significantly inhibit the CORT-induced upregulation protein of PGC-1α. RESULTS:: herein suggest that Chaihu Shugan San-containing serum can alleviate CORT-induced damage in PC12 cells, which may be related to the mitochondrial fragmentation/lipid peroxidation protection by Drp1 inhibition, as well as mitochondrial dynamics and energy metabolism mediated by PGC-1α/SIRT1 signaling pathway.
Animals ; PC12 Cells ; Rats ; Mitochondrial Dynamics/drug effects* ; Mitochondria/metabolism* ; Corticosterone/adverse effects* ; Membrane Potential, Mitochondrial/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Protective Agents/pharmacology* ; Cell Survival/drug effects*

BACKGROUND: In response to growing concerns about the health effects of quasi-millimeter waves (qMMW) used in 5th-generation wireless systems, conservative whole-body exposure thresholds based on indirect evidence have been proposed. The guidelines define a whole-body average specific absorption rate (WBA-SAR) of 4 W/kg which causes a 1 °C increase in core temperature, as the operational threshold for adverse health effects. To address the lack of direct evidence, we recently reported that a 30-minute exposure to qMMW at 4.6 W/kg resulted in a 1 °C increase in rat core temperature. Here, we further analyzed the near-threshold stress response for the first time, using biological samples from the aforementioned and additional experiments. METHODS: A total of 59 young Sprague-Dawley rats (240-322 g) were exposed to 28 GHz for 40 minutes at WBA-SARs of 0, 3.7, and 7.2 W/kg, under normal (22.5 °C, 45-55% humidity), and heat (32 °C, 70% humidity) conditions. Rats were restrained in acrylic holders for dose control. We repeatedly measured serum and urinary biomarkers of stress response, aggregated the data, and analyzed them using a single statistical mixed model to subtract the effects of sham exposure and between-subject variation. RESULTS: Sham exposure induced stress responses, suggesting an effect of restraint. After the subtraction of the sham exposure effect, 28 GHz appeared to induce stress responses as evidenced by elevated serum-free corticosterone 1 or 3 days after the exposure, which was more evident in animals with a change in rectal temperature exceeding 1 °C. Urinary-free catecholamines demonstrated an inhibitory property of 28 GHz frequency exposure on the stress response as evidenced by noradrenaline on the day of exposure. Heat exposure enhanced this effect, suggesting a possible role of noradrenaline in heat dissipation by promoting cutaneous blood flow, a notion supported by the correlation between noradrenaline levels and tail surface temperature, a critical organ for heat dissipation. CONCLUSIONS This study is the first to demonstrate that qMMW whole-body exposure can alter the stress response as indicated by corticosterone and noradrenaline at near-threshold levels. Our findings may provide insight into the biological basis of the whole-body exposure thresholds in the international guidelines.
Animals ; Rats ; Rats, Sprague-Dawley ; Male ; Restraint, Physical ; Stress, Physiological/radiation effects* ; Corticosterone/blood* ; Biomarkers/blood* ; Microwaves/adverse effects*

OBJECTIVE: To study the effect of 6-week intensive training on renal function in rats and the mechanism of exercise-induced proteinuria. METHODS: Thirty-six male SD rats, aged 6 weeks, were divided into two groups, including a control group(C,=12)and an overtraining group(M,=24). After the rats adapted to feeding for 4 d, group C did not carry out any exercise, and the M group did 6-week of increasing load swimming, 6 days a week, once a day. Started with the load of 1%weight at the beginning of the 4 week,and gradually increased (to 6% weight). Took a single urine from both groups 30 min after the end of the training. Blood was taken from the main ventral vein, and the bilateral kidneys were to be tested. The levels of tested urine protein, microalbumin and neutrophil gelatinase associated lipocalin(NGAL) was determined by using enzyme linked immunosorbent assaytest. The content of urine creatinine was tested with alkaline picric acid method,. The serum levels of colorimetric method to determine serum creatinine and urea nitrogen were determined by colorimetric method. The expression of Nephrin in renal tissue was detected by Western blot and the radioimmunoassay was used to test serum testosterone, corticosterone and renin-angiotensin system related index. RESULTS: Compared with group C, the serum testosterone/cortisone(T/C) of group M was decreased significantly (<0.01). The urine total protein(TP), microalbumin (mAlb), microalbumin/creatinine (mAlb/CRE), NGAL, blood urea nitrogen (BUN) and serum creatinine(SCr) were increased significantly (<0.01). The abnormality of glomerular structure was obvious, and the paller scores were higher. The protein expression of Nephrin was obviously down decreased (<0.01). The renin activity (Ra) and angiotension Ⅱ (Ang Ⅱ) in renal and circulating blood were decreased significantly (<0.01). CONCLUSIONS The effects of 6-week intensive training on renal function in rats and the mechanism of exercise-induced proteinuria may be that overtraining can induce the continuous excitation of Reninrenin activity in renal and circulating blood, down-regulated the expression of Nephrin, lead to abnormality of renal structure and function, and proteinuria.
Animals ; Blood Urea Nitrogen ; Corticosterone ; blood ; Creatinine ; blood ; Kidney ; physiopathology ; Male ; Membrane Proteins ; metabolism ; Physical Conditioning, Animal ; adverse effects ; Proteinuria ; Rats ; Rats, Sprague-Dawley ; Renin-Angiotensin System ; Testosterone ; blood

OBJECTIVEUsing the method of reverse transcription-polymerase chain reaction (RT-PCR) to detect the related gene expression,with a view to clarify the principal mechanism that the neuroprotection of paeoniflorin (PF).

METHODAt the seventh day, after the pretreatment of PF (0.5, 2, 10 micromol x L(-1)), with 30 min primary cultures of neurons from the cerebral cortex of 16 days old embryo rats were injured with corticosterone (200 micromol x L(-1)). After 48 h, the methods of RT-PCR was used to detect the expression of Bcl-2, Bax, Caspase-3, BDNF mRNA.

RESULTCompared with model group, the dose of PF(2, 10 micromol x L(-1)) not only can degrade the expression of Bax, Caspase-3 mRNA, but also can raise the expression of Bcl-2, BDNF mRNA notablely (P < 0.05).

CONCLUSIONThe data indicated that the principal mechanism of prophylactic neuroprotective effect of PF on corticosterone-induced neurons damages maybe due to PF can raise the expression of apoptosis-related genes Bel-2, Bax, Caspase-3 mRNA, and also ascribe to PF can raise the expression of neurotrophic factor.

Animals ; Benzoates ; pharmacology ; Brain-Derived Neurotrophic Factor ; genetics ; metabolism ; Bridged-Ring Compounds ; pharmacology ; Caspase 3 ; genetics ; metabolism ; Cells, Cultured ; Cerebral Cortex ; cytology ; drug effects ; injuries ; metabolism ; Corticosterone ; adverse effects ; Female ; Gene Expression ; drug effects ; Glucosides ; pharmacology ; Male ; Monoterpenes ; Neurons ; drug effects ; metabolism ; Neuroprotective Agents ; pharmacology ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo explore the role and mechanism of glucocorticoid (GC) in the harmful bio-effects of electromagnetic irradiation.

METHODSRats were exposed to 65 mW/cm(2) electromagnetic wave for 20 min. At 10 min, 30 min, 3 h, 12 h after irradiation, their learning and memory abilities were tested by Morris water maze. The levels of corticosterone (CORT) in serum were measured by radioimmunoprecipitation assay and the changes of total glucocorticoid receptor (GR) expression and GR nuclear translocation in rat hippocampus were measured by reverse transcription-polymerase chain reaction and Western blot.

RESULTSThe rats had learning and memory deficits at 10 min, 30 min and 3 h after irradiation, but at 12 h had no difference from the normal control. The levels of corticosterone in serum increased significantly at 10 min, 30 min, decreased at 3 h and increased significantly compared with 12 h after irradiation. GR mRNA and total GR protein expression in rat hippocampus had no significant changes at 10 min, 30 min after irradiation. At 3 h, 12 h GR mRNA expression significantly decreased by 69%, 76% respectively and GR total protein decreased by 58%, 67% respectively. There were significant differences between the two groups and the corresponding controls (P<0.05). And compared with the control, the GR nuclear translocation increased significantly at 3 h and 12 h (P<0.05).

CONCLUSIONGC may take part in the injury to learning and memory abilities after electromagnetic irradiation, and the non-genomic and genomic effects of GC may play a major role in the early and late stage, respectively.

Animals ; Corticosterone ; blood ; Electromagnetic Fields ; adverse effects ; Glucocorticoids ; blood ; Hippocampus ; metabolism ; radiation effects ; Male ; Rats ; Rats, Wistar ; Receptors, Glucocorticoid ; metabolism