Carnosic acid protects mice from high-fat diet-induced NAFLD by regulating MARCKS.

Non-alcoholic fatty liver disease (NAFLD) comprises a spectrum of liver damage characterized by abnormal hepatic fat accumulation and inflammatory response. Although the molecular mechanisms responsible for the disease are not yet fully understood, the pathogenesis of NAFLD likely involves multiple signals. The identification of effective therapeutic strategies to target these signals is of utmost importance. Carnosic acid (CA), as a phenolic diterpene with anticancer, anti-bacterial, anti-diabetic and neuroprotective properties, is produced by many species of the Lamiaceae family. Myristoylated alanine-rich C-kinase substrate (MARCKS) is a major protein kinase C (PKC) substrate in many different cell types. In the present study, wild-type C57BL/6 and MARCKS-deficient mice were randomly divided into the normal chow- or high-fat (HF) diet-fed groups. The HF diet increased the fasting glucose and insulin levels, and promoted glucose intolerance in the wild-type mice. MARCKS deficiency further upregulated intolerance, fasting glucose and insulin. The HF diet also promoted hepatic steatosis, serum alanine transaminase (ALT) and aspartate transaminase (AST) activity, inflammation and lipid accumulation in the wild-type mice. These responses were accelerated in the MARCKS-deficient mice. Importantly, increased inflammation and lipid accumulation were associated with phosphoinositide 3-kinase (PI3K)/AKT, NLR family pyrin domain containing 3 (NLRP3)/nuclear factor-κB (NF-κB) and sterol regulatory element binding protein-1c (SREBP-1c) signaling pathway activation. The mice treated with CA exhibited a significantly improved glucose and insulin tolerance. The production of pro-inflammatory cytokines and lipid accumulation were suppressed by CA. Significantly, MARCKS was reduced in mice fed the HF diet. CA treatment upregulated MARCKS expression compared to the HF group. Furthermore, the activation of the PI3K/AKT, NLRP3/NF-κB and SREBP-1c signaling pathways was inhibited by CA. Taken together, our data suggest that CA suppresses inflammation and lipogenesis in mice fed a HF diet through MARCKS regulation. Thus, CA may be prove to be a useful anti-NAFLD agent.

Identification of a sustainable two-plant diet that effectively prevents age-related metabolic syndrome and extends lifespan in aged mice.

The current system of food production is linked to both the increasing prevalence of chronic disease and the deterioration of the environment, and thereby calls for novel ways of producing nutritious foods in a sustainable manner. In the "longevity village" of Bama, China, we have identified two plant foods, hemp seed and bitter vegetable (Sonchus oleraceus), that are commonly consumed by its residents and grow abundantly in unfarmed land without fertilizers or pesticides. Here, we show that a diet composed of these two foods (the "HB diet") provides a sufficient variety of nutrients and confers significant health benefits. Aged mice allowed ad libitum access to the HB diet not only had longer life spans and improved cognitive function but were also protected against age-related metabolic syndrome, fatty liver, gut dysbiosis and chronic inflammation compared to aged mice fed a control Western diet. Furthermore, longevity-related genes (including 5'adenosine monophosphate-activated protein kinase, sirtuin 1, nuclear respiratory factor 1 and forkhead box O3) were significantly up-regulated, while aging-related genes (including mammalian target of rapamycin and nuclear factor kappa B) were down-regulated. These results demonstrate that the HB diet is capable of promoting health and longevity, and present a sustainable source of healthy foods that can help control the prevalence of chronic diseases and reduce agricultural impact on the environment.

[Evaluation of Clonorchis sinensis PPMP I antigen Cs2 recombinant protein for immunodiagnosis of clonorchiasis].

OBJECTIVE: To develop and preliminarily evaluate two immunodiagnostic methods for clonorchiasis using Clonorchis sinensis PPMP I antigen Cs2 recombinant protein (rCs2). METHODS: Using the soluble rCs2, an indirect ELISA and a colloidal-gold immuno-chromatography assay (GICA) dynamic flow strip was developed for detecting specific antibodies in serum. Serum samples from 35 egg-positive clonorchiasis patients, 33 healthy individuals, 15 schistosomiasis patients, 15 paragonimiasis westermani patients and 13 cysticercosis patients were examined by ELISA and GICA strip test. To further evaluate the diagnostic value of these two methods, eight New Zealand rabbits were randomly divided into infected group and treatment group. Each rabbit was infected with 600 C. sinensis metacercaria. Rabbits in treatment group were treated with praziquantel [150 mg/(kg x d) x 2d] individually at day 56 post-infection. ELISA and GICA strip test were used to observe the dynamic changes of specific antibodies against rCs2 in the two parallel groups during the period of 0-44 weeks. RESULTS: The sensitivity, specificity and total coincidence rate determined by the ELISA method were 71.4% (25/35), 93.4% (71/76), and 86.5% (96/111), respectively, and the cross reaction with schistosomiasis, paragonimiasis and cysticercosis patients were 1/15, 1/15, and 1/13, respectively. The sensitivity, specificity and coincidence rate in the GICA strip test were 85.7% (30/35), 92.1% (70/76), and 90.1%(100/111), respectively. In C sinensis infected rabbits, antibodies level began to increase at 4 weeks after infection, peaked at the 6th week, and declined rapidly to a lower level in the 20th week, while the changing pattern of antibodies level in the treatment group was similar with that of infected group (P > 0.05). In the GICA strip test, antibodies in two groups could be detected in 4-16 weeks. CONCLUSION: Indirect ELISA and the GICA dynamic flow strip developed in this study may be of value in the immunodiagnosis of clonorchiasis.

Characterization of spray-dried microalgal oil encapsulated in cross-linked sodium caseinate matrix induced by microbial transglutaminase.

Sodium caseinate (SC) cross-linked by microbial transglutaminase (MTGase) for encapsulating microalgal oil was investigated. Protein cross-linking was evidenced in the SDS-PAGE graph. The emulsifying properties of SC depended on the cross-linked time with MTGase. The emulsifying activity and stability indexes of SC increased with the cross-linking time of 30 to 90 min (P30 to P90), and then declined with longer cross-linked time of 180 to 420 min (P180 to P420). The P30 to P90 as wall material for microencapsulation was superior to P180 to P420 and control sample. The microcapsules prepared with P30 to P90 showed more than 97% of microencapsulation efficiency in contrast to about 90% with the P180 to P420. During storage, the microcapsules prepared with P30 to P90 exhibited higher oxidative stability as compared with other microcapsules. A sustained release of microalgal oil was observed, and core release was time dependent and affected by cross-linking degree. Results showed that the powdered microalgal oil prepared with P30 to P90 demonstrated enhanced physicochemical properties and oxidative stability. Practical Application: The novel method using cross-linked proteins as wall material induced by microbial transglutaminase in food industry for sensitive ingredients could convert microcapsules into a stable form, which would lead to its more widespread utilization as a kind of food additive.