Increased production of 8-oxo-7,8-dihydroguanine in human urine, a novel biomarker of osteoporosis.

Osteoporosis is a worldwide disease that seriously affects the quality of life and survival rate of the elderly. The detection of bone biomarkers will provide supplementary information on bone mineral density, contributing to the accurate diagnosis of osteoporosis and better health care for prevention. This study aimed to investigate the efficacy of oxidative stress markers-8-oxo-7,8-dihydroguanine (8-oxoGsn) and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodGsn) in the assessment of osteoporosis. We conducted a cross-sectional study among menopausal women with a mean (standard deviation) age of 62.967 (7.798) years old (n = 151). Participants were recruited for the bone mineral density (BMD) assessment, blood and urinary samples. Urinary 8-oxo-7,8-dihydro-2'-deoxyguanosine and 8-oxo-7,8-dihydro-guanine concentrations were measured by ultra-performance liquid chromatography and tandem mass spectrometry (UPLC-MS/MS). The urinary 8-oxoGsn/Cre value differed significantly between normal and osteoporotic participants (p < 0.001), while the 8-oxodGsn/Cre value did not (p = 0.720). Even after adjusting for the age and body mass index, the BMD was still associated with urinary 8-oxoGsn/Cre value. ROC analysis showed that 8-oxoGsn has a strong diagnostic value for osteoporosis (AUC = 0.744). The results show for the first time that 8-oxoGsn may be a biomarker for the future diagnosis of osteoporosis in women.

Berberine Attenuates Vascular Remodeling and Inflammation in a Rat Model of Metabolic Syndrome.

Berberine is a natural product that shows benefits for metabolic syndrome (MS). However, the effects of berberine on the improvement of vascular inflammation and remodeling in MS remain unclear. This study aimed to investigate whether berberine could prevent vascular remodeling and inflammation in the MS condition. A rat model of MS was established, and MS rats were divided into two groups: MS group without berberine treatment, and MSB group with berberine treatment (each group n-10). Ten normal Wistar rats were used as controls (NC group). Vascular damage was examined by transmission electron microscopy and pathological staining. Compared to the NC group, the secretion of inflammatory factors was increased and the aortic wall thicker in the MS group. The MSB group exhibited decreased secretion of inflammatory factors and improved vascular remodeling, compared to the MS group. In addition, the levels of p38 mitogen-activated protein kinase (p38 MAPK), activating transcription factor 2 (ATF-2) and matrix metalloproteinase 2 (MMP-2) were significantly decreased in the MSB group compared to the MS group. In conclusion, our data show that berberine improves vascular inflammation and remodeling in the MS condition, and this is correlated with the ability of berberine to inhibit p38 MAPK activation, ATF-2 phosphorylation, and MMP-2 expression.

Huang-lian-jie-du-tang protects rats from cardiac damages induced by metabolic disorder by improving inflammation-mediated insulin resistance.

Huang-lian-jie-du-tang (HLJDT), a traditional Chinese medicine, has been shown to improve insulin resistance (IR) induced by inflammation, a key event in the development of metabolic syndrome (MS). The present study aimed to investigate the protective effects of HLJDT on MS and explore the underlying mechanism. MS rats were established with obese-diets and treated with normal saline, aspirin or HLJDT. The myocardial lesions were identified by echocardiogram, transmission electron microscope, and Sirius-red staining. The inflammatory cytokines were measured by ELISA and real-time PCR. The activation of NF-κB, JNK, SOCS3, IRS1 and AKT in the heart was detected by immunohistochemistry and Western blot analysis. Compared with the controls, MS rats developed obvious obesity, hypertension, dyslipidemia, IR, inflammation, and cardiac damage. Moreover, phosphorylated IRS-1 at Ser307 was correlated with the activation of NF-κB, JNK and SOCS3 and the inhibition of AKT in the heart from MS rats. These data suggest that serine phosphorylation of IRS-1 in response to inflammation is mediated, in part, by NF-κB, JNK and SOCS3. Notably, HLJDT inhibited the activation of NF-κB and reduced serine phosphorylation of IRS-1. In summary, HLJDT protects myocardium from IR-mediated injury by inhibiting serine phosphorylation of IRS-1 in MS rats.

Arecoline excites the contraction of distal colonic smooth muscle strips in rats via the M3 receptor-extracellular Ca2+ influx - Ca2+ store release pathway.

Areca is a Chinese herbal medicine that is widely used for constipation. However the mechanisms of its action are not clear. We investigated the effects of arecoline, the most active component of areca, on the motility of rat distal colonic smooth muscle strips. In longitudinal muscle of distal colon (LMDC) and circular muscle of distal colon (CMDC), arecoline increased the contraction in a dose-dependent manner. Tetrodotoxin (TTX) did not inhibit the effects of arecoline. The contractile response to arecoline was completely antagonized by atropine. 4-Diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) strongly depressed the response to arecoline, but gallamine and methoctramine did not. Nifedipine, 2-aminoethoxydiphenyl borate (2-APB), and Ca2+-free Krebs solution with EGTA partly inhibited the effects of arecoline. The sum of Ca2+-free Krebs solution, EGTA, and 2-APB completely inhibited the effects of arecoline. The results show that arecoline stimulates distal colonic contraction in rats via the muscarinic (M3) receptor - extracellular Ca2+ influx - Ca2+ store release pathway. It is likely that the action of areca in relieving constipation is due to its stimulation of muscle contraction.

Tong-xin-luo capsule inhibits left ventricular remodeling in spontaneously hypertensive rats by enhancing PPAR-gamma expression and suppressing NF-kappaB activity.

BACKGROUND: Tong-xin-luo capsule (TXL), used as a traditional Chinese herb, offeres a therapeutic potential for treatment of cardiovascular diseases. It has been shown to exert a variety of pharmacological effects, including antihypertensive effects, and is able to improve ventricular remodeling. However, the mechanisms of its action are not completely understood. The aim of this study was to evaluate the molecular mechanisms of Tong-xin-luo capsule on left ventricular remodeling in spontaneously hypertensive rats (SHR). METHODS: Sixteen eight-week-old SHRs were randomized into an SHR group (n = 8) and a TXL group (n = 8) that were given Tong-xin-luo capsule (1.5 mg x kg(-1) x d(-1)). Eight Wistar Kyoto (WKY) rats fed with 0.9% NaCl served as the control group (WKY group). Systolic blood pressure (BP), body weight and heart rate were monitored once every two weeks. Ventricular remodeling was detected by histopathological examination. Nuclear factor kappa B P65 (NF-kappaB P65) and peroxisome proliferators activated receptor gamma (PPAR-gamma) protein and phosphorylated inhibitor kappa alpha (IkappaBalpha) protein were detected by immunohistochemistry and western blot respectively. The physical interaction of the P65-P50 heterodimer with IkappaBalpha and NF-kappaB were measured by co-immunoprecipitation. PPAR-gamma mRNA, collagen I mRNA and collagen III mRNA were measured by real-time PCR. RESULTS: TXL inhibited NF-kappaB P65 expression and ventricular remodeling and suppressed the activation of NF-kappaB compared with the SHR group (P < 0.01, P < 0.05). TXL reduced IkappaBalpha phosphorylation, increased expression of PPAR-gamma protein and enhanced the physical interaction of the P65-P50 heterodimer with IkappaBalpha. The mRNA expression of PPAR-gamma was enhanced but the mRNA expression of collagen I mRNA and collagen I mRNA were suppressed by TXL. CONCLUSIONS: In spontaneously hypertensive rats, TXL could inhibit ventricular remodeling induced by hypertension, and the inhibitory effect might be associated with the process of TXL increasing the expression of PPAR-gamma that could result in the inhibition of the activation of NF-kappaB.