Long-term dietary supplementation with a yang-invigorating Chinese herbal formula increases lifespan and mitigates age-associated declines in mitochondrial antioxidant status and functional ability of various tissues in male and female C57BL/6J mice.

To investigate whether Vigconic 28 (VI-28), a Yang-invigorating Chinese herbal formula, could affect survival of aging animals, male and female C57BL/6J mice were given a VI-28-supplemented diet (0.05 and 0.5%, wt/wt) starting at 36 weeks of age, until death. VI-28 dietary supplementation at 0.05% significantly increased median lifespans of both male and female mice as compared to controls. Survival enhancement was associated with protection against age-associated impairments in mitochondrial antioxidant status and functional ability in various tissues. In conclusion, VI-28 could retard the aging process in mice, probably by mitigating age-associated declines in mitochondrial antioxidant status and functional ability in tissues.

Long-term schisandrin B treatment mitigates age-related impairments in mitochondrial antioxidant status and functional ability in various tissues, and improves the survival of aging C57BL/6J mice.

Mitochondrial decay is a major cause of aging, leading to the subsequent death of aerobic organisms including humans. In the present study, we examined the effects of supplementation with schisandrin B (Sch B, a dibenzocyclooctadiene derivative isolated from the fruit of Schisandra chinensis), administered at 0.012% (w/w) of diet, starting from the age of 36 weeks, on age-dependent changes in mouse mitochondrial antioxidant status and functional ability in various tissues (brain, heart, liver, and kidney) up to the age of 120 weeks. We also monitored survival of male and female C57BL/6J mice. Aging caused progressive impairment in mitochondrial antioxidant status in various tissues, as evidenced by decreases in reduced glutathione and alpha-tocopherol levels, and Mn-superoxide dismutase activity. Impairments in mitochondrial antioxidant status were invariably associated with increases in mitochondria-driven reactive oxygen species (ROS) production in tissue homogenates, as well as decreased mitochondrial ATP-generation capacities (ATP-GCs), in all tested tissues. Diet supplementation with Sch B ameliorated impairment in mitochondrial antioxidant status during aging. The effects were more pronounced in younger than in older mice, when compared to age-matched non-supplemented controls. Sch B supplementation also suppressed mitochondria-driven ROS production and enhanced mitochondrial ATP-GC in various tissues during aging. The beneficial effects of Sch B supplementation on mitochondrial antioxidant status and functional ability were paralleled by survival improvement in aging male mice, when compared with controls. Sch B supplementation also improved the survival in female mice. In conclusion, long-term Sch B supplementation mitigated age-dependent impairments in mitochondrial antioxidant capacity and functional ability, thereby retarding the aging process in mice, particularly during early aging.

A 'Yang-Invigorating' Chinese herbal formula protects against gentamicin-induced nephrotoxicity in rats.

The effects of VI-28 (a Yang-invigorating Chinese herbal formula) treatment on the renal mitochondrial antioxidant system and susceptibility to gentamicin-induced nephrotoxicity were investigated in rats. VI-28 treatment (80 or 240 mg/kg/day x 12) enhanced the renal mitochondrial antioxidant system, as indicated by dose-dependent increases in the level/activities of reduced glutathione, Mn-superoxide dismutase, Se-glutathione peroxidase and glutathione S-transferases. VI-28 treatment protected against nephrotoxicity induced by gentamicin administration (100 mg/kg/day x 8) and the nephroprotection was associated with an enhancement in the renal mitochondrial antioxidant system. In conclusion, VI-28 treatment enhanced the renal mitochondrial antioxidant system, thereby protecting against gentamicin nephrotoxicity.

Long-term treatment with a Yang-invigorating Chinese herbal formula produces generalized tissue protection against oxidative damage in rats.

Previous work in our laboratory has shown that long-term treatment with Vigconic 28 (VI-28), a Yang-invigorating Chinese herbal formula used for the promotion of overall wellness in Chinese medicine, can enhance the mitochondrial functional ability and antioxidant capacity in various tissues of both male and female rats. To investigate whether the VI-28 treatment regimen could afford tissue protection against oxidative injury, the effects of long-term VI-28 treatment (80 or 240 mg/kg/d x 30) on oxidative stress-induced tissue damage in various organs (brain, heart, liver, and kidney) were examined in female rats. The results indicated that long-term VI-28 treatment invariably protected against oxidative tissue damage in the rat models of cerebral/myocardial ischemia-reperfusion injury, CCl4 hepatotoxicity, and gentamicin nephrotoxicity. The tissue protection was associated with increases in the levels and activities of mitochondrial antioxidant components as well as with the preservation of mitochondrial structural integrity. This was evidenced by decreases in the sensitivity of mitochondria to Ca2+-induced permeability transition, and in the levels of mitochondrial malondialdehyde production, Ca2+ loading, and cytochrome c release in the tissues examined. Interestingly, the VI-28 treatment increased red cell CuZn-superoxide dismutase (CuZn-SOD) levels, and these levels correlated positively with the degree of tissue protection afforded by long-term VI-28 treatment in rats. The generalized tissue protection afforded by long-term VI-28 treatment may have clinical implications in the prevention of age-related diseases, and VI-28 treatment may possibly delay the aging process.

Dang-Gui Buxue Tang protects against oxidant injury by enhancing cellular glutathione in H9c2 cells: role of glutathione synthesis and regeneration.

In order to investigate the biochemical mechanism of Dang-Gui Buxue Tang (DBT) involved in its cardioprotective action, the effects of DBT and related preparations on the cellular level of reduced glutathione (GSH) and on susceptibility to menadione-induced toxicity were examined in H9c2 cardiomyocytes. Treatment with herbal extract prepared from the fresh root of Astragalus membranaceus (RAM) or Angelica sinensis (RAS) alone and their combinations (D1:1-D10:1) in varying ratios of RAM to RAS (1:1 to 10:1, respectively) increased cellular GSH in a concentration-dependent manner, with the effect produced by the D5:1 extract, an authentic formula of DBT, being the most potent. The enhancement of cellular GSH was found to correlate positively with the degree of cytoprotection against menadione toxicity. Both GSH-enhancing and cytoprotective effects of DBT were largely abolished by GSH depletion as a result of buthionine sulfoximine (BSO)/phorone treatment. The DBT-induced increase in the cellular GSH level and the associated cytoprotection were also suppressed by the treatment with BSO, an inhibitor of GSH synthesis, or 1,3-bis(2-chloroethyl)-1-nitrosourea, an inhibitor of GSH regeneration. The results indicate that DBT treatment protects against oxidant injury in H9c2 cells, and that the cytoprotective action is causally related to the increase in cellular GSH level, which is likely mediated by the enhancement of GSH synthesis and regeneration.

Schisandrin B induced antioxidant response is partly mediated by cytochrome P-4502E1 catalyzed reaction in mouse liver.

In order to explore the role of cytochrome P-450 (CYP) 2E1 in schisandrin B (Sch B)-induced antioxidant and heat shock responses, the effects of Sch B treatment on hepatic mitochondrial glutathione antioxidant status (mtGAS) and heat shock protein (Hsp)25/70 expression were compared between wild-type and cyp2e1 knock-out C57B/6N mice. Cyp2e1 knock-out mice exhibited a significantly smaller degree of Sch B-induced enhancement in hepatic mtGAS when compared with the wild-type counterpart. But Hsp25/70 expression induced by Sch B was not affected. Sch B-induced enhancement of mtGAS was corroborated by the increase in hepatic mitochondrial antioxidant capacity, as assessed by in vitro measurement of oxidant production, with the enhancing effect being slightly reduced in the knock-out mice. Using liver microsomes prepared from wild-type and knock-out mice as a source of CYP, Sch B was found to be a good co-substrate for the CYP-catalyzed reaction, with the rate of NADPH oxidation observable in microsomes prepared from knock-out mice being slower. The CYP-catalyzed reaction with Sch B was associated with a concomitant production of oxidant species, with the extent of oxidant production being reduced in cyp2e1 knock-out mouse microsomes. Taken together, the results indicate that CYP2E1 is partly responsible for the hepatic metabolism of Sch B that may trigger the antioxidant response in vivo.

(-)Schisandrin B is more potent than its enantiomer in enhancing cellular glutathione and heat shock protein production as well as protecting against oxidant injury in H9c2 cardiomyocytes.

Effects of schisandrin B enantiomers ((+)Sch B and (-)Sch B) treatment on cellular reduced glutathione (GSH) level and heat shock protein (Hsp)25/70 production were investigated in H9c2 cardiomyocytes. (+)Sch B and (-)Sch B at 6.25 muM produced a time-dependent and biphasic change in cellular GSH level and Hsp25/70 production, with the stimulatory effect of (-)Sch B being more potent. The GSH- and Hsp-enhancing effects were accompanied by a parallel cytoprotection against xanthine oxidase/xanthine-induced toxicity, with the biphasic time course of (+)Sch B- or (-)Sch B-induced protection being superimposed with that of the increase in GSH level but not Hsp25/70 production. The results indicate that (-)Sch B produces more potent enhancing effects on cellular GSH and Hsp production as well as protection against oxidative injury than (+)Sch B in cardiomyocytes.

Effects of schisandrin B enantiomers on cellular glutathione and menadione toxicity in AML12 hepatocytes.

Effects of schisandrin B enantiomer ((+)Sch B and (-)Sch B) treatment on the reduced cellular glutathione (GSH) level and susceptibility to menadione-induced toxicity were investigated and compared in AML12 hepatocytes. (+)Sch B or (-)Sch B treatment at 6.25 micromol/l produced a time-dependent change in cellular GSH level, with the maximal stimulation occurring 16 h after dosing. (+)Sch B/(-)Sch B pretreatment for 16 h dose-dependently protected against menadione toxicity, with the maximum degree of protection observable at 6.25 micromol/l and the extent of protection afforded by (-)Sch B being larger than that of (+)Sch B. The cytoprotection was associated with a parallel enhancement in cellular GSH level in both non-menadione (control) and menadione-intoxicated cells. While the GSH depletion produced by buthionine sulfoximine/phorone treatment largely abrogated the cytoprotective action of (+)Sch B/(-)Sch B, it almost completely abolished the GSH-enhancing effect of (+)Sch B and (-)Sch B in both control and menadione-treated cells. Both (+)Sch B and (-)Sch B treatments increased the GSH reductase activity in control and menadione-treated cells, with the stimulatory action of (-)Sch B being more potent than that of (+)Sch B in the control condition. (+)Sch B and (-)Sch B also enhanced the gamma-glutamate cysteine ligase activity in menadione-intoxicated cells. The results indicate that (-)Sch B is more effective than (+)Sch B in enhancing cellular GSH and protecting against oxidant injury in hepatocytes.

Chronic schisandrin B treatment improves mitochondrial antioxidant status and tissue heat shock protein production in various tissues of young adult and middle-aged rats.

The effects of chronic schisandrin B (Sch B) treatment (10 mg/kg/dayx15) on mitochondrial antioxidant status and sensitivity to Ca2+-induced permeability transition, as well as tissue heat shock protein (Hsp)25/70 production were examined in various tissues (brain, heart, liver, skeletal muscle) of young adult and middle-aged female rats. Age-dependent impairment in mitochondrial antioxidant status, as assessed by levels/activities of antioxidant components (reduced glutathione, alpha-tocopherol, Se-glutathione peroxidase and Mn-superoxide dismutase) and the extent of reactive oxygen species generation in vitro, was observed in brain, heart, liver and skeletal muscle tissues. While tissue Hsp25 levels remained relatively unchanged with aging, the Hsp70 level was increased in both brain and heart tissues of middle-aged rats. Chronic Sch B treatment was able to enhance mitochondrial antioxidant status and the resistance to Ca2+-induced mitochondrial permeability transition in an age-independent manner in various tissues of rats. However, Hsp25 and Hsp70 levels were only increased in young adult rats. The Sch B-induced enhancement of mitochondrial protective parameters in the heart was associated with the protection against myocardial ischemia-reperfusion injury in both young adult and middle-aged rats. The results suggest that chronic Sch B treatment may be beneficial for reversing the mitochondrial changes with aging and enhancing the heat shock response.

A yang-invigorating Chinese herbal formula enhances mitochondrial functional ability and antioxidant capacity in various tissues of male and female rats.

The practice of traditional Chinese medicine (TCM) always emphasizes the prevention of diseases and delaying the onset of senility. In this regard, the maintenance of a balance of Yin and Yang-two opposing components involved in life activities as exemplified by the antagonistic action of the sympathetic and parasympathetic nervous systems-is essential in achieving a healthy condition. Previous studies have shown that long-term treatment with a Yang-invigorating Chinese herbal formula (VI-28) could increase red cell CuZn-superoxide dismutase (SOD) activity in male human subjects. In the present study, we examined the effects of chronic VI-28 treatment (80 and 240 mg/kg/day for 30 days) on red cell CuZn-SOD activity as well as mitochondrial functional ability and antioxidant components in various tissues of male and female rats. The results indicated that VI-28 treatment increased red cell CuZn-SOD activity as well as mitochondrial ATP generation capacity, reduced glutathione and alpha-tocopherol levels, and Mn-SOD activity in brain, heart, liver, and skeletal muscle tissues in both male and female rats to varying extents. The VI-28?induced increase in mitochondrial antioxidant capacity in various tissues was evidenced by the significant reduction in the extent of reactive oxygen species generation assessed by in vitro measurement. The red cell CuZn-SOD activities correlated positively with tissue mitochondrial antioxidant component levels/activity. The beneficial effect of VI-28 treatment on mitochondrial functional ability and antioxidant capacity may have clinical implications in the prevention of age-related diseases.

Role of cytochrome P-450 in schisandrin B-induced antioxidant and heat shock responses in mouse liver.

In order to explore the role of cytochrome P-450 (P-450) in schisandrin B (Sch B)-induced antioxidant and heat shock responses, the effect of 1-aminobenzotriazole (ABT, a broad spectrum inhibitor of P-450) on hepatic mitochondrial glutathione antioxidant status (mtGAS) and heat shock protein (Hsp)25/70 expression was examined in Sch B-treated mice. The non-specific and partial inhibition of cytochrome P-450 (P-450) by ABT pretreatment significantly caused a protraction in the time-course of Sch B-induced enhancement in hepatic mitGAS and Hsp25/70 expression in mice. Using mouse liver microsomes as a source of P-450, Sch B, but not dimethyl diphenyl bicarboxylate (a non-hepatoprotective analog of Sch B), was found to serve as a co-substrate for the P-450-catalyzed NADPH oxidation reaction, with a concomitant production of oxidant species. Taken together, the results suggest that oxidant species generated from P-450-catalyzed reaction with Sch B may trigger the antioxidant and heat shock responses in mouse liver.

Pharmacological basis of 'Yin-nourishing' and 'Yang-invigorating' actions of Cordyceps, a Chinese tonifying herb.

Cordyceps sinensis (Berk.) Sacc. (Cordyceps), a popular Chinese tonifying herb, was revered for being both 'Yin-nourishing' and 'Yang-invigorating' in Chinese medicine. In order to establish the pharmacological basis for the 'Yin-nourishing' and 'Yang-invigorating' action of Cordyceps, the effects of wild and cultured Cordyceps on concanavalin A (Con A)-stimulated splenocytes, an in vitro bioassay for 'Yin-nourishment', and myocardial ATP generation capacity, an ex vivo bioassay for 'Yang-invigoration', were investigated in mice. The results indicated that methanolic extracts of wild and cultured Cordyceps enhanced both the Con A-stimulated splenocyte proliferation in vitro and myocardial mitochondrial ATP generation ex vivo in mice, with no significant difference in potency of action between the two types of Cordyceps. While the immuno-potentiating effect was associated with the increase in interleukin II production, the stimulation of myocardial ATP generation was paralleled by an enhancement in mitochondrial electron transport. When compared with typical 'Yin' and 'Yang' tonifying Chinese herbs, Cordyceps was found to possess both 'Yin-nourishing' and 'Yang-invigorating' activities, with a lower potency in both modes of action. The pharmacological characterization of Cordyceps by means of contemporary bioassays is consistent with the time-honored clinical observation from Chinese herbalists.

Pharmacological basis of 'Yang-invigoration' in Chinese medicine.

The 'Yin-Yang' theory is an ancient Chinese philosophy that underlies the practice of traditional Chinese medicine. Although Yang-tonic herbs tend to boost body function possibly through enhancing the mitochondrial oxidative processes, the Yin property (i.e. antioxidant potential) of these herbs can also play a role in safeguarding mitochondrial ATP generation. The pharmacological basis of 'Yang-invigoration' by Chinese tonic herbs might be due primarily to the enhancement of mitochondrial ATP generation.

Hepatoprotective mechanism of schisandrin B: role of mitochondrial glutathione antioxidant status and heat shock proteins.

In this study, the time course of schisandrin B- (Sch B-) induced changes in hepatic mitochondrial glutathione antioxidant status (mtGAS) and heat shock protein (HSP) 25/70 induction was examined to study their differential roles in the hepatoprotection afforded by Sch B pretreatment against carbon tetrachloride (CCl(4)) toxicity in mice. Dimethyl diphenyl bicarboxylate (DDB), a nonhepatoprotective analog of Sch B, was also included for comparison. The results indicate that Sch B treatment (2 mmol/kg) produced maximum enhancement in hepatic mtGAS and increases in both hepatic HSP 25 and HSP 70 levels at 24 h after dosing. While the extent of hepatoprotection afforded by Sch B pretreatment against CCl(4) was found to correlate inversely with the elapsed time postdosing, the protective effect was associated with the ability to sustain mtGAS and/or HSP 70 levels in a CCl(4)-intoxicated condition. On the other hand, DDB (2 mmol/kg) treatment, which did not sustain mtGAS and HSP 70 level, could not protect against CCl(4) toxicity. Abolition of the Sch B-mediated enhancement of mtGAS by buthionine sulfoximine/phorone did not completely abrogate the hepatoprotective action of Sch B. The results indicate that Sch B pretreatment independently enhances mtGAS and induces HSP 25/70 production, particularly under conditions of oxidative stress, thereby protecting against CCl(4) hepatotoxicity.

Metformin protects against carbon tetrachloride hepatotoxicity in mice.

In the present study, the hepatoprotective effect of metformin (Met), a dimethylbiguanide anti-hyperglycemic, was examined in a mouse model of liver damage induced by chronic repeated administration of carbon tetrachloride (CCl(4)) (5 microl/kg, twice a week for 12 weeks). Met, when given orally in drinking water at an estimated daily dose of 25 or 50 mg/kg for 10 weeks starting 2 weeks after CCl(4) challenge, protected against CCl(4) hepatotoxicity. The results indicate that the hepatoprotection afforded by Met treatment at a dose of 25 mg/kg against CCl(4) toxicity may at least in part be mediated by the enhancement of mitochondrial glutathione redox status.