Ecological and pharmacognostical characteristics in Ephedra saxatilis in the Yarlung Zangbo River Valley of southeastern Tibetan Plateau, China.

In the Yarlung Zangbo River Valley of the southeastern Tibetan Plateau, China (29°07'49.5"N, 92°41'11.0"E, 3256 m above sea level), we found an Ephedra saxatilis community in the xeric steppe with shrubland vegetation habitat of the broad alluvial plain of the river with soil having relatively higher water-soluble cation (Ca2+, 8.62; K+, 1.94; Mg2+, 2.38 mmol/100 g dry soil weight) and nitrogen (NO3-, 21.78; NH4+, 1.82 mmol/100 g dry soil weight) content. The ranges of ephedrine and pseudoephedrine in 13 E. saxatilis samples were as follows: ephedrine, not detected-3.03 of dry weight (%DW) and pseudoephedrine, not detected-1.36%DW. The 13 E. saxatilis plants collected in the study area showed intraspecific variability of ephedrine and pseudoephedrine with 6 samples containing ephedrine and pseudoephedrine, 6 samples containing only ephedrine, and 1 sample containing only pseudoephedrine.

Relationship between ephedrine alkaloid profile in Ephedra gerardiana and soil characteristics of glacial landforms in southeastern Tibetan Plateau, China.

In the Kaluxung River catchment of the southeastern Tibetan Plateau in China, we identified three Ephedra gerardiana communities on different soils and glacial landforms from 4842 to 4899 m above sea level: a moraine community located on constantly collapsing sandy gravel alpine steppe slopes with exposed bedrock on the outer slope of the terminal moraine of the Qiangyong Glacier on Mt. Kaluxung; an outwash plain community located on a gentle alpine steppe slope with exposed bedrock at the terminal end of the outwash plain in the glacial valley of the southeast side of Mt. Noijinkangsang; and a river terrace community located in an alpine meadow on a rock-scattered flat river terrace along a glacier-fed river in the outwash plain in the glacial valley of the southeast side of Mt. Noijinkangsang. Based on the finding of identical DNA sequences of the intergenic spacers of chloroplast trnT-trnF and trnS-trnfM regions for all Ephedra specimens examined in this study, the E. gerardiana in this study were considered to comprise a genetically homogeneous population. Analysis of the relationship between ephedrine alkaloid profiles of these three communities and soil characteristics showed that the river terrace community in wet alpine meadow had significantly lower ephedrine content than did the moraine and outwash plain communities in dry alpine steppe (moraine community, 1.52 ± 0.44; outwash plain community, 1.42 ± 0.68; river terrace community, 0.33 ± 0.65%DW), but pseudoephedrine content showed the reverse pattern (moraine community, 0.86 ± 0.30; outwash plain community, 0.73 ± 0.60; river terrace community, 1.50 ± 0.71%DW). In addition, total alkaloid (ephedrine and pseudoephedrine) content in the river terrace community (1.83 ± 0.24%DW) was significantly lower than that in the moraine community (2.38 ± 0.64%DW) and outwash plain community (2.15 ± 0.55%DW).

Anti-Inflammation Effect of Small Molecule Oligopeptides Prepared from Panax ginseng C. A. Meyer in Rats.

The present study was designed to investigate the anti-inflammatory effects of ginseng oligopeptides (GOPs). For the anti-inflammatory activity, dextran-induced paw edema and granuloma models were used in Sprague-Dawley rats (180⁻200 g, 12 weeks old, n = 10). Rats were treated orally with GOPs (0, 62.5, 125, 250 and 500 mg/kg) for prophylaxis. In the granuloma model, the levels of NO, Tumor necrosis factor-α (TNF-α), interleukin IL-ß, and interleukin IL-10 in serum were evaluated. In addition, in the edema model, the level of TNF-α, prostaglandin E2 (PGE2), Leukotriene D4 (LTD4), and the platelet activating factor (RAF) in paw tissue were detected. PCR assessed the effect of GOPs on the expression of MAPK and NF-κB. The results showed that oral administration of GOPs inhibited inflammation caused by cotton pellet and dextran. GOPs significantly inhibited the edema formation via MAPK and NF-κB. These findings suggested that GOPs have a beneficial effect on acute and chronic inflammation, and the mechanism possibly mediated by inhibiting gene expression involved in inflammation and downregulating inflammatory mediators.

Hypoglycemic Effects of Oat Oligopeptides in High-Calorie Diet/STZ-Induced Diabetic Rats.

The study was aimed to determine whether treatment with oat oligopeptides (OOPs) could modulate hyperglycemia related to type 2 diabetes mellitus (T2DM) in Sprague⁻Dawley (SD) rats. Diabetic SD rats modeling by a joint effect of high-calorie diet for 45 days and twice intraperitoneal injection of 30 mg/kg streptozotocin at one-week interval were observed with or without OOPs administration (0.25, 0.50, 1.00, and 2.00 g/kg Body Weight) for 12 weeks. Fasting blood glucose (FBG), oral glucose test tolerance (OGTT), serum insulin, level of antioxidant, and hepatic enzymes were measured. In addition, frequency of micturition was recorded in this study for the first time. It was observed that the administration of OOPs (2.00 g/kg Body Weight) resulted in a significant decrease (p < 0.05) in FBG since 6th week and a significant decrease (p < 0.05) in the OGTT-AUC on 6th and 10th week. In addition, the administration of OOPs (2.00 g/kg Body Weight) reduced HOMA-IR index and 24-h urine volume significantly (p < 0.05) whereas increased SOD activity significantly (p < 0.05). These results suggested that OOPs may have a hypoglycemic effect in diabetic rats.

Ginseng oligopeptides protect against irradiation-induced immune dysfunction and intestinal injury.

Intestinal injury and immune dysfunction are commonly encountered after irradiation therapy. While the curative abilities of ginseng root have been reported in prior studies, there is little known regarding its role in immunoregulation of intestinal repairability in cancer patients treated with irradiation. Our current study aims to closely examine the protective effects of ginseng-derived small molecule oligopeptides (Panax ginseng C. A. Mey.) (GOP) against irradiation-induced immune dysfunction and subsequent intestinal injury, using in vitro and in vivo models. Expectedly, irradiation treatment resulted in increased intestinal permeability along with mucosal injury in both Caco-2 cells and mice, probably due to disruption of the intestinal epithelial barrier, leading to high plasma lipopolysaccharide (LPS) and pro-inflammatory cytokines levels. However, when the cells were treated with GOP, this led to diminished concentration of plasma LPS and cytokines (IL-1 and TNF-α), suggesting its dampening effect on inflammatory and oxidative stress, and potential role in restoring normal baseline intestinal permeability. Moreover, the Caco-2 cells treated with GOP showed high trans-epithelial electrical resistance (TEER) and low FITC-dextran paracellular permeability when compared to the control group. This could be explained by the higher levels of tight junction proteins (ZO-1 and Occludin) expression along with reduced expression of the apoptosis-related proteins (Bax and Caspase-3) noticed in the GOP-treated cells, highlighting its role in preserving intestinal permeability, through prevention of their degradation while maintaining normal levels of expression. Further confirmatory in vivo data showed that GOP-treated mice exhibited high concentrations of lymphocytes (CD3+, CD4+, CD8+) in the intestine, to rescue the irradiation-induced damage and restore baseline intestinal integrity. Therefore, we propose that GOP can be used as an adjuvant therapy to attenuate irradiation-induced immune dysfunction and intestinal injury in cancer patients.

Ginseng (Panax ginseng Meyer) oligopeptides regulate innate and adaptive immune responses in mice via increased macrophage phagocytosis capacity, NK cell activity and Th cells secretion.

Traditionally used as a restorative medicine, ginseng (Panax ginseng Meyer) has been the most widely used and acclaimed herb in Chinese communities for thousands of years. To investigate the immune-modulating activity of ginseng oligopeptides (GOP), 420 healthy female BALB/c mice were intragastrically administered distilled water (control), whey protein (0.15 g per kg body weight (BW)), and GOP 0.0375, 0.075, 0.15, 0.3 and 0.6 g per kg BW for 30 days. Blood samples from mice were collected from the ophthalmic venous plexus and then sacrificed by cervical dislocation. Seven assays were conducted to determine the immunomodulatory effects of GOP on innate and adaptive immune responses, followed by flow cytometry to investigate spleen T lymphocyte sub-populations, multiplex sandwich immunoassays to investigate serum cytokine and immunoglobulin levels, and ELISA to investigate intestinally secreted immunoglobulin to study the mechanism of GOP affecting the immune system. Our results showed that GOP was able to enhance innate and adaptive immune responses in mice by improving cell-mediated and humoral immunity, macrophage phagocytosis capacity and NK cell activity. Notably, the use of GOP revealed a better immune-modulating activity compared to whey protein. We conclude that the immune-modulating activity might be due to the increased macrophage phagocytosis capacity and NK cell activity, and the enhancement of T and Th cells, as well as IL-2, IL-6 and IL-12 secretion and IgA, IgG1 and IgG2b production. These results indicate that GOP could be considered a good candidate that may improve immune functions if used as a dietary supplement, with a dosage that ranges from 0.3 to 0.6 g per kg BW.

Beneficial Effects of Small Molecule Oligopeptides Isolated from Panax ginseng Meyer on Pancreatic Beta-Cell Dysfunction and Death in Diabetic Rats.

To determine whether treatment with ginseng oligopeptides (GOPs) could modulate hyperglycemia related to type 2 diabetes mellitus (T2DM) in rats induced by high-fat diet and low doses of alloxan, type 2 diabetes was induced in male Sprague-Dawley (SD) rats by injecting them once with 105 mg/kg alloxan and feeding them high-carbohydrate/high-fat diet with or without GOP administration (0.125, 0.5, and 2.0 g/kg Body Weight) for 7, 24, and 52 weeks. Oral glucose test tolerance (OGTT), plasma glucose, serum insulin, level of antioxidant, and beta cell function were measured. Morphological observation and immunohistochemistry study of insulin of islets was performed by light microscopy. The insulin level and the expression of NF-κB and Bcl-2 family in pancreatic islets were also detected by Western blot analysis. In addition, survival time and survival rate were observed. After the treatment, the abnormal OGTT were partially reversed by GOPs treatment in diabetic rats. The efficacy of GOPs was manifested in the amelioration of pancreatic damage, as determined by microscopy analysis. Moreover, GOPs treatment increased the normal insulin content and decreased the expression of the NF-κB-signaling pathway. Compared with those in the control model, the survival time and rate were significantly longer. It is suggested that GOPs exhibit auxiliary therapeutic potential for diabetes.

Visual cortex activation decrement following cochlear implantation in prelingual deafened children.

OBJECTIVE: Visual take-over of the auditory cortex in prelingual deaf children has been widely reported. However, there have been few studies on visual cortex plasticity after cochlear implantation (CI). In this study, we investigated the hypothesis that extrinsic auditory stimulation following CI in prelingual deafened children can induce visual cortex plasticity. METHOD: Visual evoked potentials (VEPs) were recorded in 37 CI children (4 groups with different use times) and 8 control subjects, in response to sound and nonsound stimuli. Latency and amplitude were analyzed for the P1, N1 and P2 components on the Oz electrode. Comparisons of VEP were conducted between the sound and nonsound stimuli and among different groups in order to view evidence of visual cortex reorganization. RESULTS: The latency of the P2 component was significantly longer at the occipital site (Oz) in CI 0M than those in the other four groups. After the effect of age was excluded, a significant negative correlation was found between CI usage and P2 latency of nonsound stimuli. Occipital P1N1 latency and P1 amplitude were not affected by group or stimulus category. However, the N1 and P2 amplitudes were significantly larger in response to a sound stimulus than to a nonsound stimulus. CONCLUSION: Our findings suggest that P2 latency develops with CI usage and may be a biomarker of visual cortex plasticity.

Suppression of TNF-α and free radicals reduces systematic inflammatory and metabolic disorders: Radioprotective effects of ginseng oligopeptides on intestinal barrier function and antioxidant defense.

Irradiation therapy is markedly associated with intestinal injure and oxidant stress. This study aimed to investigate the effects of ginseng (Panax ginseng C.A. Mey.) oligopeptides (GOP) on irradiation-induced intestinal injury and antioxidant defense in mice. BALB/c mice (8 weeks old) were randomly divided into six groups: vehicle control, irradiation control (IR), IR+whey protein [0.30 g/kg body weight (BW)], IR+GOP 0.15 g/kg BW, IR+GOP 0.30 g/kg BW and IR+GOP 0.60 g/kg BW. Postirradiation 30-day survival trial, white blood cells count and bone marrow hematopoietic system damage were performed to identify the injury degree induced by irradiation. Then, histopathology analysis was observed and intestinal permeability in vivo was quantified with fluorescein isothiocyanate-dextran. The enzyme-linked immunosorbent assay was used to determine antioxidant ability, plasma inflammatory cytokines, diamine oxidase (DAO) and endotoxin (LPS) levels. The immunohistochemistry assay was used to analyze the expression levels of tight junction proteins. We found that GOP-treated mice exhibited lower concentrations of plasma LPS and DAO and decreased instructors of inflammatory and oxidative stress which were linked to the lower intestinal permeability and higher tight junction proteins expression. The blockage of GOP was linked with the reduction of TNF-α and free radicals. The 15-day pretreatment of GOP could exhibit radioprotective effects, and another 15-day posttreatment benefited the quick repair of irradiation-induced injury. We confirm that GOP would exhibit effective therapeutic value on attenuating irradiation-induced hematopoietic, gastrointestinal and oxidative injury in cancer patients.

Anti-Fatigue Effects of Small Molecule Oligopeptides Isolated from Panax ginseng C. A. Meyer in Mice.

Panax ginseng C. A. Meyer (ginseng) is an edible and medicinal Chinese herb, which is often used in Asian countries for physical fitness. Ginseng is reported to have a wide range of biological activity and pharmaceutical properties. There were more studies on ginsenosides and polysaccharides, but fewer studies on ginseng oligopeptides (GOP), which are small molecule oligopeptides isolated from ginseng. The present study was designed to evaluate the anti-fatigue effects of GOP in mice and explore the possible underlying mechanism. Mice were randomly divided into four experimental sets for the detection of different indicators. Each set of mice were then divided into four groups. The control group was administered distilled water, and three GOP intervention groups were administered 125, 250, and 500 mg/kg of body weight, respectively, of GOP by gavage each day. After 30 days of GOP treatment, it was observed that GOP could significantly increase the forced swimming time, enhance lactate dehydrogenase (LDH) activity and hepatic glycogen levels, and retard the accumulation of serum urea nitrogen (SUN) and blood lactic acid (BLA) in mice. GOP also markedly ameliorated fatigue-induced alterations of inoxidative stress biomarkers and antioxidant enzymes. Notably, GOP increased the mRNA expression of mitochondrial biogenesis factors and mitochondrial DNA content in skeletal muscles of mice. These results suggest that GOP possess anti-fatigue effects, which may be attributed to the inhibition of oxidative stress and the improvement of mitochondrial function in skeletal muscles. GOP could be a novel natural agent for relieving exercise fatigue.

Sustaining Effect of Intensive Nutritional Intervention Combined with Health Education on Dietary Behavior and Plasma Glucose in Type 2 Diabetes Mellitus Patients.

Diabetes mellitus is very common in elderly Chinese individuals. Although nutritional intervention can provide a balanced diet, the sustaining effect on at-home dietary behavior and long-term plasma glucose control is not clear. Consequently, we conducted a long-term survey following one month of experiential nutritional intervention combined with health education. Based on the Dietary Guidelines for a Chinese Resident, we found that the food items met the recommended values, the percentages of energy provided from fat, protein, and carbohydrate were more reasonable after one year. The newly formed dietary patterns were "Healthy", "Monotonous", "Vegetarian", "Japanese", "Low energy", and "Traditional" diets. The 2h-PG of female participants as well as those favoring the "Japanese diet" decreased above 12 mmol/L. Participants who selected "Japanese" and "Healthy" diets showed an obvious reduction in FPG while the FPG of participants from Group A declined slightly. "Japanese" and "Healthy" diets also obtained the highest DDP scores, and thus can be considered suitable for T2DM treatment in China. The results of the newly formed dietary patterns, "Japanese" and "Healthy" diets, confirmed the profound efficacy of nutritional intervention combined with health education for improving dietary behavior and glycemic control although health education played a more important role. The present study is encouraging with regard to further exploration of comprehensive diabetes care.

Anti-rheumatoid arthritic effects of Saussurea involucrata on type II collagen-induced arthritis in rats.

Saussurea involucrata (SI) has long been used under the herbal name "snow lotus" for treatment of inflammation and pain-related diseases in traditional Chinese medicine. The present study aimed to evaluate the pharmacological effects of SI on collagen II (CII)-induced arthritis in rats. Rats with collagen II (CII)-induced arthritis were orally administered SI (420 mg kg(-1)) for 40 consecutive days. Histopathological examination indicated that SI alleviates infiltration of inflammatory cells and synovial hyperplasia and slows joint destruction. SI intervention reduced the serum levels of RF, COMP, CRP and anti-CII IgG. Results also showed that SI is a potential therapeutic agent for alleviating the severity of the disease based on the reduced arthritic index. It was concluded that SI can ameliorate inflammation and joint destruction in CIA rats.

[Study on the prevalence of dyslipidemia and associated dietary risk factors among adults in Shunyi District of Beijing].

OBJECTIVE: To study the prevalence of dyslipidemia and explore dietary related factors of dyslipidemia among residents aged over 18-year-old in Shunyi District of Beijing. METHODS: A stratified cluster random sampling was used in this study which select the residents who aged above 18 years old in Shunyi District to do a well-designed questionnaire and physical examination, the cholesterol (TC), triglycemide (TG), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) were measured and statistical processed in order to analyze the differences of dietary influencing factors between the dyslipidemia and normal population. RESULTS: The detection rates of dyslipidemia and combined dyslipidemia in Shunyi adults were 49.3% and 2.7%. The adults' intake of energy, fat and carbohydrate in rural areas was significantly higher than that in urban residents (P < 0.05). The intake of sodium, vegetable oil and salt all exceeded the standard of Dietary Guidelines for Chinese. There were significant difference in the contribute rate of fat and carbohydrate in total energy between the the dyslipidemia and normal population. The multi-factor Logistic Analysis showed that higher BMI, waist circumference, weight, fat, cholesterol were the risk factors of dyslipidemia, dietary niacin and vitamin C are protective factors for adults' dyslipidemia. CONCLUSION: The dyslipidemia among residents in Shunyi District of Beijing and their Dietary Structure is closely related. The unreasonable dietary structure and lifestyle maybe the main factor of dyslipidemia.

Effect of dietary nucleotides on immune function in Balb/C mice.

This study investigated the effect of dietary nucleotides (NTs) on immune function in female Balb/C mice, which randomly distributed into six groups: one control group, one NF-free (NF) control group and four NT groups. NTs ranged from 0.0025% to 0.64%. Compared with the control group, the NF could significantly weaken the activity of T lymphocytes and macrophages, as well as decreased the activity of B lymphocytes and NK cell. NF significantly decreased the ratio of CD4(+)/CD8(+), whereas, it increased Tr percentage. In comparison with the NF group, the concentration of serum IL-2 and IL-4 showed an increase trend. Meanwhile, the granular cell macrophages colony stimulating factor (GM-CSF) increased significantly in the 0.04% NT group. The ratio of Th1/Th2 also showed an increasing trend after the supplements of NTs. There were no significant differences between the control and 0.04% NT group. Nevertheless, no significant differences in weight gain and lymphoid organ indices were observed in our study. These results indicate that NT supplements can prevent hypoimmunity which result from NF diet. 0.04% NTs is the healthy optimal supply proportion in mice diet.

[Investigation on the dietary iron intake of infants from four month-old to one year-old in Shunyi District of Beijing].

OBJECTIVE: To understand the present status of dietary iron intake of infants from 4 to 12 month-old in urban and rural areas of Shunyi District of Beijing, and to provide scientific basis for their supplementary foods. METHODS: Two hundred and sixty-six infants were selected and investigated with a 3-day (72h) dietary record questionary. RESULTS: The average dietary iron intake of 4 - 5 month-old infants has achieved to the Dietary Reference Intakes, and no significant difference was observed between the intakes in urban and rural areas (P > 0.05). The proportion of infants whose dietary iron intake was higher than the Adequate Intakes (AI) of iron was just 19.8% among the studied infants in rural and 36. 9% in urban areas (P < 0.01). There was no significant difference on breastfeeding rates in rural and urban groups (P > 0.05). The main dietary iron sources were from cereals, fruits, eggs, vegetables and meat. CONCLUSION: The dietary iron intake of 6 - 12 month-old infants in Shunyi was significantly insufficient. Encouraging mothers to go on fully breastfeeding for at least 6 months, as well as giving supplementary foods rich in iron at the right time according to the state of infants.

Oral administration of marine collagen peptides from Chum Salmon skin enhances cutaneous wound healing and angiogenesis in rats.

BACKGROUND: A wound is a clinical entity which often poses problems in clinical practice. The present study was aimed to investigate the wound healing potential of administering marine collagen peptides (MCP) from Chum Salmon skin by using two wound models (incision and excision) in rats. RESULTS: Ninety-six animals were equally divided into the two wound models and then within each model animals were randomly divided into two groups: vehicle-treated group and 2 g kg(-1) MCP-treated group. Wound closure and tensile strength were calculated. Collagen deposition was assessed by Masson staining and hydroxyproline measurement. Angiogenesis was assessed by immunohistological methods. MCP-treated rats showed faster wound closure and improved tissue regeneration at the wound site, which was supported by histopathological parameters pertaining to wound healing. MCP treatment improved angiogenesis and helped form thicker and better organised collagen fibre deposition compared to vehicle-treated group. CONCLUSION: The results show the efficacy of oral MCP treatment on wound healing in animals.

Prevention of retinoic acid-induced early craniofacial abnormalities by vitamin B12 in mice.

OBJECTIVE: The purpose of the present study was to identify the potential effect of prenatal vitamin B12 administration on retinoic acid (RA)-induced early craniofacial abnormalities in mice and to investigate the possible mechanisms by which vitamin B12 reduces malformations. DESIGN: In our study, whole embryo culture was used to explore the effect of vitamin B12 on mouse embryos during the critical period of organogenesis. All embryos were exposed to 0.4 µM RA and different concentrations of vitamin B12 and scored for their growth in the branchial region at the end of a 48-hour culture period. The endothelin-1 (ET-1)/dHAND protein expression levels in the first branchial arch were investigated using an immunohistochemical method. RESULTS: In the whole embryo culture, 100 and 10 µM vitamin B12 dose-dependently prevented branchial region malformations and decreased craniofacial defects by 90.5% and 77.3%, respectively. ET-1 and dHAND protein levels were significantly increased in vitamin B12-supplemented embryos compared to the RA-exposed group in embryonic branchial region. CONCLUSIONS: These results suggest that vitamin B12 may prevent RA-induced craniofacial abnormalities via prevention of an RA-induced decrease of ET-1 and dHAND protein levels in the branchial region during the organogenic period. This study may shed new light on preventing craniofacial abnormalities.

Protective effect of a marine oligopeptide preparation from chum salmon (Oncorhynchus keta) on radiation-induced immune suppression in mice.

BACKGROUND: A marine oligopeptide preparation (MOP) obtained from Chum Salmon (Oncorhynchus keta) by the method of enzymatic hydrolysis, has been found to enhance the innate and adaptive immunities through stimulation of the secretion of cytokines in mice. The current study aimed to further investigate the protective effect of MOP on radiation-induced immune suppression in mice. RESULTS: Female ICR mice (6-8 weeks old) were randomly divided into three groups, i.e. blank control, irradiation control and MOP (1.350 g kg(-1) body weight) plus irradiation-treated group. MOP significantly increased the survival rate and prolonged the survival times for 30 days after irradiation, and lessened the radiation-induced suppression of T- or B-lymphocyte proliferation, resulting in the recovery of cell-mediated and humoral immune functions. This effect may be produced by augmentation of the relative numbers of radioresistant CD(4) (+) T cells, enhancement of the level of immunostimulatory cytokine, IL-12, reduction of the level of total cellular NF-κB through the induction of IκB in spleen and inhibition of the apoptosis of splenocytes. CONCLUSION: We propose that MOP be used as an ideal adjuvant therapy to alleviate radiation-induced injuries in cancer patients.

Marine collagen peptides prepared from chum salmon (Oncorhynchus keta) skin extend the life span and inhibit spontaneous tumor incidence in Sprague-Dawley Rats.

To observe the effects of marine collagen peptides (MCPs) prepared from chum salmon (Oncorhynchus keta) skin on life span and spontaneous tumor incidence, Sprague-Dawley rats were fed diets supplemented with MCP at concentrations of 0%, 2.25%, 4.5%, and 9% (wt/wt) from the age of 4 weeks until natural death. There were 40 rats in each group (male:female ratio = 1:1). The results showed that the MCP did not significantly influence body weight or food consumption of rats of either sex throughout the life span; it did dose-dependently inhibit the age-related decrease in the activities of antioxidant enzymes and the age-related increase in the levels of lipid peroxidation product in both sexes. MCP notably increased the mean life span, the life span of the last 30% of the survivors, and the maximal life span; it decreased overall spontaneous tumor incidence of both sexes with significance in the 4.5% and 9% MCP-treated male groups and 9% MCP-treated female group. Compared to the control group, the incidence of death from tumors was decreased in MCP groups in comparison with the control group of both sexes. Therefore, we concluded that MCPs dose-dependently increase life span and decrease spontaneous tumor incidence in Sprague-Dawley rats. Moreover, the antioxidative property of MCPs may be responsible for the increased life span and protection against tumor development.

The protective effects of long-term oral administration of marine collagen hydrolysate from chum salmon on collagen matrix homeostasis in the chronological aged skin of Sprague-Dawley male rats.

To investigate the long-term effects of marine collagen hydrolysate (MCH) from Chum Salmon skin on the aberrant collagen matrix homeostasis in chronological aged skin, Sprague-Dawley male rats of 4-wk-old were orally administrated with MCH at the diet concentrations of 2.25% and 4.5% for 24 mo. Histological and biochemical analysis revealed that MCH had the potential to inhibit the collagen loss and collagen fragmentation in chronological aged skin. Based on immunohistochemistry and western blot analysis, collagen type I and III protein expression levels in MCH-treated groups significantly increased as compared with the aged control group. Furthermore, quantitative real-time polymerase chain reaction and western blot analysis showed MCH was able to increase the expressions of procollagen type I and III mRNA (COL1A2 and COL3A1) through activating Smad signaling pathway with up-regulated TGF-ßRII (TßRII) expression level. Meanwhile, MCH was shown to inhibit the age-related increased collagen degradation through attenuating MMP-1 expression and increasing tissue inhibitor of metalloproteinases-1 expression in a dose-dependent manner. Moreover, MCH could alleviate the oxidative stress in chronological aged skin, which was revealed from the data of superoxide dismutase activity and the thiobarbituric acid reactive substances level in skin homogenates. Therefore, MCH was demonstrated to have the protective effects on chronological skin aging due to the influence on collagen matrix homeostasis. And the antioxidative property of MCH might play an important role in the process.