Hyperacmosin R, a New Decarbonyl Prenylphloroglucinol with Unusual Spiroketal Subunit from Hypericum acmosepalum.

Two previously undescribed polycyclic polyprenylated acylphloroglucinols, hyperacmosins R-S (1-2), were obtained from the aerial parts of Hypericum acmosepalum. Their structures were elucidated by extensive spectroscopic analysis and electronic circular dichroism calculation (ECD). Compound 1 featured an unprecedented 5,8-spiroketal subunit as well as the loss of C-2' carbonyl in the phloroglucinol ring. In addition, compounds 1 and 4 showed weak hepatoprotective activity against paracetamol-induced HepG2 cell damage at 10 µm. The plausible biosynthetic pathway of 1 was proposed via a retro-Clasisen reaction and decarboxylation.

Polycyclic polyprenylated acylphloroglucinols from Hypericum beanii and their hepatoprotective activity.

Twenty-seven polycyclic polyprenylated acylphloroglucinols (PPAPs) with diverse skeletons, including seven previously undescribed ones (hyperbeanins A-G), were isolated from the aerial parts of Hypericum beanii. Their structures were established by comprehensive analysis of NMR, HRESIMS, and experimental electronic circular dichroism (ECD) spectra. Hyperbeanin A was a monocyclic polyprenylated acylphloroglucinols (MPAPs) with an unusual spiro-fused cyclopropane ring. Four of the isolated compounds showed obvious hepatoprotective activity against paracetamol-induced HepG2 cell damage at 10 µM. The present results suggested that these compounds would be potential hepatoprotective agents. In addition, the plausible biogenetic pathways of hyperbeanins A-G were proposed, which gave an insight for future biomimetic synthesis of them.

[Kinetic Release Characteristics of Organic Phosphorus of Sediment-water and Water Quality Risks].

To reveal the characteristics of organic phosphorus release from lake sediments and its potential impact on water quality, six lake sediments from Yunnan Plateau and the middle and lower reaches of the Yangtze River in China were selected. We studied the differences in the kinetics of dissolved organic phosphorus (DOP) and dissolved inorganic phosphorus (SRP) release from sediments. The effects of organic phosphorus morphology and dissolved organic matter (DOM) characteristics on sediment phosphorus release were investigated, and the water quality risks of sediment DOP release were discussed. The results showed that:① the release kinetics of sediment DOP and SRP were similar; both followed the second-order kinetic model, starting with a rapid release phase, followed by a slow release, and the release curve gradually leveled off and reached the maximum release. ② The release of organic phosphorus was related to organophosphorus morphology and organic matter. Active organic phosphorus (LOP) and medium active organic phosphorus (MLOP) were the DOP forms mainly released into the overlying water during the rapid release phase. The proportion of LOP and MLOP to total organic phosphorus (DTP) decreased in the late release stage, whereas the proportion of non-active organic phosphorus (NLOP) increased; further, the degree of humification and aromaticity of organic matter gradually increased with phosphorus release, and its activity decreased, resulting in a slower release rate at the later stage. ③ Compared with that of SRP, the risk of DOP release was higher, accounting for 47%-77% of the total amount of DTP. It was also found that the higher the nutrient level of the lake, the greater the release of DOP and the higher the water quality risk. Therefore, not only the release of inorganic phosphorus but also that of organic phosphorus should be of concern in the process of phosphorus release from lake sediments to prevent the underestimation of phosphorus release and water quality risk.

Four new polyprenylated acylphloroglucinol derivatives from Hypericum beanii.

Two new polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperbeanins P-Q (1-2), and two new biosynthetic precursors, hyperbeanins R-S (3-4), were isolated from Hypericum beanii, together with three known analogs (5-7). Compound 1 was one of type A PPAPs featured with unusual bicyclo[5.3.1]hendecane core. The structures of isolates were established by NMR spectroscopic methods, experimental electronic circular dichroism (ECD) spectra and comparisons with known compounds. Compounds 5 and 6 showed obvious hepatoprotective activity at 10 µM against paracetamol-induced HepG2 cell damage.

[Chemical constituents from Hypericum curvisepalum].

This study explored the chemical constituents of the aerial part of Hypericum curvisepalum. Sixteen compounds were isolated from the 95% ethanol extract of H. curvisepalum with various chromatographic techniques, including a new prenylated phenyl polyketide, mysorenone D(1). Other compounds were mysorenone-A(2), mysorenone-C(3), mysorenone-B(4), peplidiforone A(5), 4-methoxy-3-(2-methylbut-3-en-2-yl)-6-phenyl-2H-pyran-2-one(6), hyperenone-A(7), 4-(3,3-dimethylallyl)oxy-6-phenyl-α-pyrone(8), peplidiforone B(9), elegaphenone(10), hypercohin A(11), hyperisampsin G(12), spathulenol(13), quercetin(14), ß-sitosterol(15), and ß-amyrin(16).

[Chemical constituents of Myripnois dioica].

To study the chemical constituents of the aerial parts of Myripnois dioica. Twelve compounds were separated from the 95% ethanol extract of M. dioica by using various chromatographic techniques. Their stuctures were identified on the basis of their physicochemical properties and spectral data as 8-desoxyurospermal A(1), zaluzanin C(2), dehydrozaluzanin C(3), glucozaluzanin C(4), macrocliniside B(5), macrocliniside I(6), taraxinic acid-14-O-ß-D-glucopyranoside(7), ainsliaside B(8), apigenin(9), luteolin(10), apigenin-7-O-ß-D-glucopyranoside(11), and luteolin-7-O-ß-D-glucopyranoside(12). Except for compound 8, the other compounds were isolated from this genus for the first time. Compound 8 was found to decrease blood glucose level properly in alloxan-induced diabetic mice.

Salvianolic Acid a prevents the pathological progression of hepatic fibrosis in high-fat diet-fed and streptozotocin-induced diabetic rats.

Type 2 diabetes patients have an increased risk of developing hepatic fibrosis. Salvianolic acid A (SalA) has been reported to be a strong polyphenolic anti-oxidant and free radical scavenger. The aim of the present study was to evaluate the effect of SalA on the pathological progression of hepatic fibrosis in high-fat diet (HFD)-fed and streptozotocin (STZ)-induced diabetic rats and to clarify the underlying mechanisms. Type 2 diabetic animal model with hepatic fibrosis was developed by a high-sucrose, HFD and low-dose STZ injection (i.p.). Diabetic rats were randomly divided into SalA group (0.3 mg/kg/day) and diabetic control groups fed with a HFD. After administration for four months, SalA reversed the hyperlipidemia and reduced hepatic triglyceride (TG). Hematoxylin-Eosin (HE) and Picro acid-Sirius red staining results indicated that SalA significantly alleviated the lesions of hepatic steatosis and fibrosis, with the reduction of type I and III collagens. The expression of α-smooth-muscle-actin (α-SMA) and transforming growth factor ß1 (TGF-ß1) in the liver were markedly down-regulated by SalA treatment. TUNEL staining showed that SalA reduced apoptosis in hepatocytes. In addition, SalA improved hepatic mitochondrial respiratory function in diabetic rats. Taken together, these findings demonstrated that SalA could prevent the pathological progression of hepatic fibrosis in HFD-fed and STZ-induced diabetic rats. The underlying mechanisms may be involved in reducing oxidative stress, suppressing α-SMA and TGF-ß1 expression, as well as exerting anti-apoptotic and mitochondria-protective effects.

[Effects of the effective component group of Chinese herbal medicine Xiaoxuming Decoction on brain mitochondria in rats with chronic cerebral ischemia].

OBJECTIVE: To investigate the effects of the effective component group of Xiaoxuming Decoction (XXM), a compound traditional Chinese herbal medicine, on cerebral mitochondria in rats with chronic cerebral ischemia. METHODS: Rats were subjected to permanent bilateral common carotid artery occlusion to induce chronic cerebral ischemia. Then, the rats with chronic cerebral ischemia were randomly divided into five groups: model group, extract of Ginkgo biloba group and low-, medium- and high-dose effective component group of XXM groups. Another 11 rats without common carotid artery occlusion were used as a sham control. Gradient centrifugation was used to obtain the mitochondria from the rat brain. Clark oxygen electrode method was used to determine mitochondrial respiratory function. Photometric determination was used to measure mitochondrial swelling. Rodamine 123 was used to measure mitochondrial membrane potential. Western blotting was used to detect mitochondrial apoptosis. RESULTS: Compared with the sham group, the mitochondria dysfunction was caused by chronic cerebral ischemia associated with the decrease of oxidative phosphorylation parameters and the mitochondrial membrane potential, the increase of the mitochondrial degree, the elevation of reactive oxygen species level, the decrease in Bcl-2/Bax ratio, and the release of cytochrome c. The effective component group of XXM could reduce mitochondrial damage induced by chronic cerebral ischemia by improving the indexes mentioned above. CONCLUSION: The effective component group of Xiaoxuming Decoction can protect brain mitochondrial homeostasis and improve the function of mitochondria in rats with chronic cerebral ischemia, which may be the mechanism of its protection against chronic cerebral ischemia.

Coptisine exert cardioprotective effect through anti-oxidative and inhibition of RhoA/Rho kinase pathway on isoproterenol-induced myocardial infarction in rats.

OBJECTIVE: Because myocardial infarction is a major cause of morbidity and mortality worldwide, protecting the heart from the ischemia is the focus of intense research. Coptisine is an isoquinoline alkaloid extracted form Coptidis Rhizoma. This study aims to elucidate if coptisine is responsible for cardioprotection using myocardial infarction (MI) rat models and investigate its potential mechanism of action. METHODS: Myocardial infarction was produced in rats with 85 mgkg(-1) isoproterenol administered subcutaneously twice at an interval of 24 h. The rats were randomized into 7 groups: (I) Normal; (II) ISO; (III) ISO+fasudil; (IV) ISO+isosorbide dinitrate (ISDN) and (V-VII) ISO+coptisine (25, 50 and 100 mgkg(-1)). Cardiac function and markers of cardiac ischemic were assessed after MI. RESULTS: Rats pretreated with coptisine (25, 50 and 100 mgkg(-1)) for 21 days and received subcutaneously injected with ISO (85 mgkg(-1)) on the 20th and 21st day at an interval of 24 h. The results suggested that coptisine has strong antioxidant activity, and it can maintain cell membrane integrity, ameliorate mitochondrial respiratory dysfunction, reduce myocardial cells apoptosis, inhibit RhoA/ROCK expression induced by high-dose isoproterenol administration. CONCLUSIONS: Coptisine provided cardioprotection in a model of myocardial infarction, and therefore should be considered as a novel adjunctive therapy for attenuating myocardial damage.

Baicalein exerts neuroprotective effects in 6-hydroxydopamine-induced experimental parkinsonism in vivo and in vitro.

Baicalein, a flavonoid obtained from the root of Chinese medicinal herb Scutellaria baicalensis, has been shown to exert a protective effect on neurons against several neuronal insults. The aim of this study was to explore the neuroprotective effect of baicalein in 6-hydroxydopamine (6-OHDA)-induced experimental parkinsonism in vitro and in vivo. In in vitro experiments, we found that baicalein (0.5, 5 microg/mL) could significantly ameliorate the 6-OHDA-induced SH-SY5Y cell apoptosis from 31.56% in the 6-OHDA group to 18.90%, 21.61% respectively, and also promote neurite outgrowth of PC12 cell. In in vivo experiments, baicalein had no effect on apomorphine (APO)-induced rotations, but it could significantly attenuate muscle tremor of 6-OHDA-lesioned rats. The burst frequency and amplitude are 13.43%, 35.18% compared to 6-OHDA group. Moreover, baicalein treatment could also increase tyrosine hydroxylase (TH)-positive neurons to 265.52% of the 6-OHDA group. The neuroprotective action of baicalein was coincident with an attenuated astroglial response within the substantia nigra. Neuroprotective effect of baicalein as demonstrated by the increasing the number of dopaminergic neurons may have been, in part, caused by anti-apoptotic, pro-differentiation and anti-inflammatory mechanisms of baicalein. Therefore, baicalein can be a promising candidate for prevention or treatment of Parkinson's disease, owing to its anti-apoptotic, pro-differentiation and anti-inflammatory action.

Neuroprotective effect of baicalein against MPTP neurotoxicity: behavioral, biochemical and immunohistochemical profile.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes the damage of dopaminergic neurons as seen in Parkinson's disease (PD). Oxidative stress has been implicated in the pathogenesis of PD. Baicalein, isolated from the traditional Chinese herbal medicine Huangqin (Scutellaria baicalensis Georgi), has been shown to have antioxidant effects. Here we investigated the effect of baicalein on MPTP-induced neurotoxicity in mice. Pretreatment with baicalein for a week was followed by challenge with MPTP for 4 consecutive days; the subsequent behavioral, biochemical and immunohistochemical manifestations in mice were determined and compared to those in untreated mice and mice challenged only with MPTP. The present study showed that baicalein could improve the abnormal behavior in MPTP-treated mice. The protective effect may be caused by increasing the levels of DA and 5-HT in the striatum, increasing the counts of dopaminergic neurons, inhibiting oxidative stress and the astroglia response. These results suggest that baicalein possesses potent neuroprotective activity and may be a potential anti-Parkinson's disease drug that is worthy of further study.