Farnesoid X receptor activation is required for the anti-inflammatory and anti-oxidative stress effects of Alisol B 23-acetate in carbon tetrachloride-induced liver fibrosis in mice.

Previous studies have shown that Alisol B 23-acetate (23ABA) had potent liver-protection effects, however, its roles and potential mechanisms in carbon tetrachloride (CCl4)-induced liver fibrosis remain to be determined. The present study aimed to investigate the effects of 23ABA on CCl4-induced liver fibrosis and tried to elucidate the underlying mechanisms by focusing on regulating of farnesoid X receptor (FXR). In vivo study found that 23ABA alleviated the CCl4-induced liver injury, and showed no obvious systemic toxicity on mice. 23ABA inhibited the collagen production, decreased sera levels of hyaluronic acid (HA) and procollagen type III (PC-III), lowered mRNA expression of α-smooth muscle actin (α-SMA), fibronectin, collagen I and collagen III in livers of mice. 23ABA inhibited the mRNA expressions and the sera levels of interleukin-6 (IL-6), IL-1ß, and tumor necrosis factor-α (TNF-α), as well as decreased the expression of cyclooxygenase 2 (COX-2) in fibrotic livers of mice. Besides, 23ABA decreased levels of reactive oxygen species (ROS) and malondialdehyde (MDA), increased glutathione (GSH) level, enhanced activities of superoxide dismutase (SOD) and glutathione reductase (GR) as well as increased mRNA expression of nuclear factor-E2-related factor 2 (Nrf2), glutamate-cysteine ligase, catalytic subunit (GCLC) and glutamate-cysteine ligase, modifier subunit (GCLM). Further study showed that the anti-liver injury and anti-fibrotic effects of 23ABA were abrogated by FXR antagonist guggulsterone (GS) in vivo. In addition, the inhibition effects of 23ABA on liver inflammation and oxidative stress were also weakened by treatment with GS in CCl4-induced fibrotic mice livers. In conclusion, the protective effects of 23ABA against CCl4-induced liver injury and fibrosis, due to FXR-mediated regulation of liver inflammation and oxidative stress.

ALS mutations in both human skeletal muscle and motoneurons differentially affects neuromuscular junction integrity and function.

There is evidence for the involvement of human skeletal muscle (hSKM) in ALS neuromuscular junction (NMJ) dysfunction. However, the specific avenue by which the hSKM contributes to NMJ disruption is not well understood due to limited human-based studies performed to investigate the subject. Thus, hSKM and human motoneurons (hMN) generated from induced pluripotent stem cells of healthy individuals (WT) and ALS patients with two different SOD1 mutations were integrated into functional NMJ systems to investigate and compare the pathological contribution of the hSKM and hMN to ALS NMJ disruption. Morphological assessment of ALS NMJs demonstrated reduced acetylcholine receptor clustering in the post-synaptic membrane of co-cultures with ALS hSKM (hSKMSOD1-hMNWT and hSKMSOD1-hMNSOD1). Significantly reduced functional NMJ numbers, NMJ stability, contraction fidelity and increased fatigue index were observed in all ALS co-cultures compared to WT. However, these disease phenotypes were comparatively more severe in microphysiologic systems with hSKMSOD1-hMNWT or hSKMSOD1-hMNSOD1 than those with hSKMWT-hMNSOD1 co-cultures. Results from this study affirm that the inherent pathological defects in ALS hSKM, independent of motoneurons, significantly contributes to NMJ dysfunction. As such, therapeutically targeting the ALS hSKM may be just as, if not more critical than, the hMN in alleviating disease phenotypes and attenuating disease progression.

Validation of an adipose-liver human-on-a-chip model of NAFLD for preclinical therapeutic efficacy evaluation.

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease and strongly correlates with the growing incidence of obesity and type II diabetes. We have developed a human-on-a-chip model composed of human hepatocytes and adipose tissue chambers capable of modeling the metabolic factors that contribute to liver disease development and progression, and evaluation of the therapeutic metformin. This model uses a serum-free, recirculating medium tailored to represent different human metabolic conditions over a 14-day period. The system validated the indirect influence of adipocyte physiology on hepatocytes that modeled important aspects of NAFLD progression, including insulin resistant biomarkers, differential adipokine signaling in different media and increased TNF-α-induced steatosis observed only in the two-tissue model. This model provides a simple but unique platform to evaluate aspects of an individual factor's contribution to NAFLD development and mechanisms as well as evaluate preclinical drug efficacy and reassess human dosing regimens.

A Human-Based Functional NMJ System for Personalized ALS Modeling and Drug Testing.

Loss of the neuromuscular junction (NMJ) is an early and critical hallmark in all forms of ALS. The study design was to develop a functional NMJ disease model by integrating motoneurons (MNs) differentiated from multiple ALS-patients' induced pluripotent stem cells (iPSCs) and primary human muscle into a chambered system. NMJ functionality was tested by recording myotube contractions while stimulating MNs by field electrodes and a set of clinically relevant parameters were defined to characterize the NMJ function. Three ALS lines were analyzed, 2 with SOD1 mutations and 1 with a FUS mutation. The ALS-MNs reproduced pathological phenotypes, including increased axonal varicosities, reduced axonal branching and elongation and increased excitability. These MNs formed functional NMJs with wild type muscle, but with significant deficits in NMJ quantity, fidelity and fatigue index. Furthermore, treatment with the Deana protocol was found to correct the NMJ deficits in all the ALS mutant lines tested. Quantitative analysis also revealed the variations inherent in each mutant lines. This functional NMJ system provides a platform for the study of both fALS and sALS and has the capability of being adapted into subtype-specific or patient-specific models for ALS etiological investigation and patient stratification for drug testing.

A multiplexed in vitro assay system for evaluating human skeletal muscle functionality in response to drug treatment.

In vitro systems that mimic organ functionality have become increasingly important tools in drug development studies. Systems that measure the functional properties of skeletal muscle are beneficial to compound screening studies and also for integration into multiorgan devices. To date, no studies have investigated human skeletal muscle responses to drug treatments at the single myotube level in vitro. This report details a microscale cantilever chip-based assay system for culturing individual human myotubes. The cantilevers, along with a laser and photo-detector system, enable measurement of myotube contractions in response to broad-field electrical stimulation. This system was used to obtain baseline functional parameters for untreated human myotubes, including peak contractile force and time-to-fatigue data. The cultured myotubes were then treated with known myotoxic compounds and the resulting functional changes were compared to baseline measurements as well as known physiological responses in vivo. The collected data demonstrate the system's capacity for screening direct effects of compound action on individual human skeletal myotubes in a reliable, reproducible, and noninvasive manner. Furthermore, it has the potential to be utilized for high-content screening, disease modeling, and exercise studies of human skeletal muscle performance utilizing iPSCs derived from specific patient populations such as the muscular dystrophies.

Long-Term Electrical and Mechanical Function Monitoring of a Human-on-a-Chip System.

The goal of human-on-a-chip systems is to capture multi-organ complexity and predict the human response to compounds within physiologically relevant platforms. The generation and characterization of such systems is currently a focal point of research given the long-standing inadequacies of conventional techniques for predicting human outcome. Functional systems can measure and quantify key cellular mechanisms that correlate with the physiological status of a tissue, and can be used to evaluate therapeutic challenges utilizing many of the same endpoints used in animal experiments or clinical trials. Culturing multiple organ compartments in a platform creates a more physiologic environment (organ-organ communication). Here is reported a human 4-organ system composed of heart, liver, skeletal muscle and nervous system modules that maintains cellular viability and function over 28 days in serum-free conditions using a pumpless system. The integration of non-invasive electrical evaluation of neurons and cardiac cells and mechanical determination of cardiac and skeletal muscle contraction allows the monitoring of cellular function especially for chronic toxicity studies in vitro. The 28 day period is the minimum timeframe for animal studies to evaluate repeat dose toxicity. This technology could be a relevant alternative to animal testing by monitoring multi-organ function upon long term chemical exposure.

Stem cell derived phenotypic human neuromuscular junction model for dose response evaluation of therapeutics.

There are currently no functional neuromuscular junction (hNMJ) systems composed of human cells that could be used for drug evaluations or toxicity testing in vitro. These systems are needed to evaluate NMJs for diseases such as amyotrophic lateral sclerosis, spinal muscular atrophy or other neurodegenerative diseases or injury states. There are certainly no model systems, animal or human, that allows for isolated treatment of motoneurons or muscle capable of generating dose response curves to evaluate pharmacological activity of these highly specialized functional units. A system was developed in which human myotubes and motoneurons derived from stem cells were cultured in a serum-free medium in a BioMEMS construct. The system is composed of two chambers linked by microtunnels to enable axonal outgrowth to the muscle chamber that allows separate stimulation of each component and physiological NMJ function and MN stimulated tetanus. The muscle's contractions, induced by motoneuron activation or direct electrical stimulation, were monitored by image subtraction video recording for both frequency and amplitude. Bungarotoxin, BOTOX® and curare dose response curves were generated to demonstrate pharmacological relevance of the phenotypic screening device. This quantifiable functional hNMJ system establishes a platform for generating patient-specific NMJ models by including patient-derived iPSCs.

Evaluation of Holistic Treatment for ALS Reveals Possible Mechanism and Therapeutic Potential.

There has been a tremendous amount of research into the causes of Amyotrophic Lateral Sclerosis (ALS), but yet very few treatment options beyond amelioration of symptoms. A holistic approach has shown anecdotal evidence of slowing disease progression and this treatment, known as the Deanna protocol (DP), postulates that ALS is a metabolic disease caused by glutamate that induces toxicity. In this study, glutamate exposure to human motoneurons was investigated and found not to significantly affect cell viability or electrophysiological properties. However, varicosities were observed in axons suggestive of transport impairment that was dose dependent for glutamate exposure. Surprisingly, a subset of the components of the DP eliminated these varicosities. To verify this finding a human SOD1 patient-derived iPSC line was examined and significant numbers of varicosities were present without glutamate treatment, compared to the iPSC control, indicating the possibility of a common mechanism despite different origins for the varicosities. Importantly, the DP ameliorated these varicosities by over 70% in the patient derived cells as well. These results are consistent with much of the literature on ALS and give hope for treatment not only for arresting disease progression using compounds considered safe but also the potential for restoration of function.

Multi-Organ toxicity demonstration in a functional human in vitro system composed of four organs.

We report on a functional human model to evaluate multi-organ toxicity in a 4-organ system under continuous flow conditions in a serum-free defined medium utilizing a pumpless platform for 14 days. Computer simulations of the platform established flow rates and resultant shear stress within accepted ranges. Viability of the system was demonstrated for 14 days as well as functional activity of cardiac, muscle, neuronal and liver modules. The pharmacological relevance of the integrated modules were evaluated for their response at 7 days to 5 drugs with known side effects after a 48 hour drug treatment regime. The results of all drug treatments were in general agreement with published toxicity results from human and animal data. The presented phenotypic culture model exhibits a multi-organ toxicity response, representing the next generation of in vitro systems, and constitutes a step towards an in vitro "human-on-a-chip" assay for systemic toxicity screening.

Regulatory role of miR-125a/b in the suppression by selenium of cadmium-induced apoptosis via the mitochondrial pathway in LLC-PK1 cells.

Cadmium (Cd), a toxic heavy metal, is known to induce kidney damage and renal tubular dysfunction. Our previous studies have indicated that selenium (Se), as an essential trace element, protects against Cd-induced nephrotoxicity via the mitochondrial apoptotic pathway in vivo and in vitro. The available evidence suggests that the expression of miRNAs is altered after Cd exposure. However, the regulatory effects of miRNAs on Cd-induced apoptosis and on the suppression by Se of Cd-induced apoptosis remain unclear. The present study aimed to explore the effects of miRNAs on the suppression by Se of Cd-induced apoptosis in LLC-PK1 cells. miR-125a and miR-125b were downregulated in response to Cd exposure but were upregulated in the Se pretreatment group. Over-expression and low expression of miR-125a/b were simulated by their mimics and inhibitors, respectively. Both Se and over-expression of miR-125a/b attenuated Cd-induced apoptosis through significant enhancement of the anti-apoptotic protein Bcl-2, reduction of the pro-apoptotic proteins Bax and Bak, the release of cytochrome c and the inactivation of caspase-9 and caspase-3. The effects of downregulation of miR-125a/b on apoptosis were similar to those of Cd treatment, and both effects were inhibited by Se. Moreover, miR-125a/b were observed to target Bak and caspase-3 directly. In summary, miR-125a/b play an important role in the suppression of Cd-induced apoptosis by Se via the mitochondrial pathway in LLC-PK1 cells.

Investigation on vitamin D knowledge, attitude and practice of university students in Nanjing, China.

OBJECTIVE: To investigate university students' knowledge, attitudes and practice (KAP) regarding vitamin D. DESIGN: The students were requested to answer a questionnaire related to vitamin D and sun exposure. The consumption frequency of foods rich in vitamin D was assessed. Additionally, the intake of vitamin D-containing supplements was recorded. SETTING: A medical university in Nanjing, China. SUBJECTS: Five hundred and fifteen medical students were included. RESULTS: The highest rate of correct responses for the quiz was 68·0 %, while the lowest was 9·6 %. Most students lacked sun exposure because they did not want to get tanned; 82·7 % of students used some sun protection and sunscreen use was more popular in the female group. The consumption frequency of foods rich in vitamin D was low and 5·6 % of the students used vitamin D supplements. The students' knowledge on vitamin D was derived mainly from the media and health professionals. Most of the students were interested to know more about vitamin D. CONCLUSIONS: The present study suggested that medical students had little knowledge and unfavourable behaviours. They should get more health education through the media and health professionals. It is advisable to increase their consumption of foods rich in vitamin D.

Repurposed biological scaffolds: kidney to pancreas.

Advances in organ regeneration have been facilitated by gentle decellularization protocols that maintain distinct tissue compartments, and thereby allow seeding of blood vessels with endothelial lineages separate from populations of the parenchyma with tissue-specific cells. We hypothesized that a reconstituted vasculature could serve as a novel platform for perfusing cells derived from a different organ: thus discordance of origin between the vascular and functional cells, leading to a hybrid repurposed organ. The need for a highly vascular bed is highlighted by tissue engineering approaches that involve transplantation of just cells, as attempted for insulin production to treat human diabetes. Those pancreatic islet cells present unique challenges since large numbers are needed to allow the cell-to-cell signaling required for viability and proper function; however, increasing their number is limited by inadequate perfusion and hypoxia. As proof of principle of the repurposed organ methodology we harnessed the vasculature of a kidney scaffold while seeding the collecting system with insulin-producing cells. Pig kidneys were decellularized by sequential detergent, enzymatic and rinsing steps. Maintenance of distinct vascular and collecting system compartments was demonstrated by both fluorescent 10 micron polystyrene microspheres and cell distributions in tissue sections. Sterilized acellular scaffolds underwent seeding separately via the artery (fibroblasts or endothelioma cells) and retrograde (murine ßTC-tet cells) up the ureter. After three-day bioreactor incubation, histology confirmed separation of cells in the vasculature from those in the collecting system. ßTC-tet clusters survived in tubules, glomerular Bowman's space, demonstrated insulin immunolabeling, and thereby supported the feasibility of kidney-to-pancreas repurposing.

Liquiritigenin Potentiates the Inhibitory Effects of Cisplatin on Invasion and Metastasis Via Downregulation MMP-2/9 and PI3 K/AKT Signaling Pathway in B16F10 Melanoma Cells and Mice Model.

Liquiritigenin (LQ) is a flavanone extracted from glycyrrhizae. Previous studies have demonstrated that LQ possesses antimigration properties in HELA and A549 cells. The present research, as an extension of our earlier ones, investigated whether LQ can enhance the antimigration and antiinvasion effect of cis-diamine dichloroplatinum (CDDP) in B16F10 melanoma cell. The data indicated that LQ (25, 50, 100, 200 µM) combined with CDDP (2 µM) significantly reduced B16F10 cell viability compared to CDDP (2 µM)-treated only. The different doses of LQ combined with CDDP significantly suppressed cell migration (21.5%, 49.6%, 75.6%) and cell invasion (26.2%, 51.4%, 69.5%) compared with CDDP-treated alone, suggesting that LQ enhance the inhibition action of CDDP on cell migration and invasion. Moreover, LQ/CDDP combination led to the downregulation of protein expression of MMP-2/9, PI3 K, p-AKT, and upregulated PTEN protein level that play an important role in tumor metastasis progression. Further study demonstrated the enhancement effect of LQ on CDDP suppressing lung metastasis in a mice model being inoculated by the B16F10 melanoma cells. In conclusion, the results suggested that LQ plays an intensive role on CDDP suppressing invasion and metastasis through regulating the PI3 K/AKT signal pathway and suppressing the protein expression of MMP-2/9.

Determination of liquiritigenin by ultra high performance liquid chromatography coupled with triple quadrupole mass spectrometry: Application to a linear pharmacokinetic study of liquiritigenin in rat plasma.

A simple, sensitive and rapid ultra high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method has been developed and validated for the quantification of liquiritigenin, a promising anti-tumor agent. Liquiritigenin and the internal standard were separated on an Agilent Extend C18 column and eluted with a gradient mobile phase system of acetonitrile and water. The analysis was performed on a negative ionization electrospray mass spectrometer via multiple reaction monitoring (MRM). Transitions of m/z 255.0→119.0 for liquiritigenin and m/z 269.0→117.0 for the IS were monitored. One-step protein precipitation with acetonitrile was used to remove impurities and extract the analytes from plasma. The method had a chromatographic run time of 4.5min and a good linearity in the range of 1-1000ng/mL. The precision (R.S.D.) of intra-day and inter-day ranged from 4.54 to 10.65% and 5.94 to 13.81%, respectively; while the accuracy of intra-day and inter-day ranged from 104.06 to 109.28% and 94.98 to 112.05%. The recovery and stability were also within the acceptable limits. The validated method was applied to a linear pharmacokinetic study of liquiritigenin in rat plasma for the first time.

The protective effects of selenium on cadmium-induced oxidative stress and apoptosis via mitochondria pathway in mice kidney.

Selenium, an essential trace element, showed the significant protective effects against kidney damage induced by some heavy metals. Our previous research have found that the protection effects of selenium on ROS mediated-apoptosis by mitochondria dysfunction in cadmium (Cd)-induced LLC-PK1 cells. The present study as a continuation of our earlier one to investigate the protective effects and mechanism of selenium on Cd-induced apoptosis of kidney in vivo. Cadmium exposure increased the production of reactive oxygen species (ROS) and altered the levels of oxidative stress related biomarkers in kidney tissue. A concomitant by the loss of mitochondrial membrane potential, cytochrome c release and regulation of VDAC, Bcl-2 and Bax were observed. Apoptotic nature of cell death is confirmed by activation of caspase-3, which is also supported by histological examination. During the process, selenium played a beneficial role against Cd-induced renal damage. Pretreatment with selenium partially blocked Cd-induced ROS generation, inhibited Cd induced mitochondrial membrane potential collapse, prevented cytochrome c release, inhibited caspase activation and changed the level of VDAC, Bcl-2 and Bax. Combining all, results suggest that selenium has an ability to inhibit mitochondrial apoptotic pathway in oxidative stress mediated kidney dysfunction caused by cadmium.

Methylenetetrahydrofolate reductase C677T polymorphism is associated with estimated glomerular filtration rate in hypertensive Chinese males.

BACKGROUND: Plasma level of total homocysteine (tHcy) is negatively correlated with kidney function in general population. However, the causal mechanism of this correlation is poorly understood. The purpose of this study is to investigate the association of methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism, which is a major genetic determinant of the plasma tHcy level, with estimated glomerular filtration rate (eGFR) in Chinese. METHODS: A total of 18 814 hypertensive patients (6,914 males, 11,900 females) were included in the study. RESULTS: Association between the eGFR and MTHFR C677T genotype was examined by sex-specific regression analyses. In males, TT genotype was associated with 1.37 ml/min/1.73 m(2) decrease in eGFR (p = 0.004) and with an increased risk (OR = 1.32, p = 0.008) for the lowest quintile of eGFR after adjusting for age, BMI, and blood pressures. However, such association was not observed in females (p > 0.05). This association suggests MTHFR C677T polymorphism may play a role in the regulation of eGFR in males. CONCLUSIONS: MTHFR 677 T is a risk allele for decreased kidney function in Chinese males, implicating this gene in the pathogenesis of chronic kidney disease (CKD).

The protection of selenium on cadmium-induced inhibition of spermatogenesis via activating testosterone synthesis in mice.

Selenium (Se) is an essential trance element in testis. However, the potential protective effects of Se against cadmium (Cd)-induced reproductive toxicity remained to be elucidated. Male ICR mice were orally administered by gavage with Na2SeO3 (0.1, 0.2, 0.4 mg/kg BW) for 1h prior to CdCl2 (5 mg/kg BW) alone or in combination for 15, 25 or 35 days. Cd exposure caused a significant decrease in body weight, sperm concentration and motility as well as plasma testosterone level which was accompanied by decreased antioxidant enzymatic activity of SOD and GSH-Px and by increased lipid peroxidation (as malondialdehyde, MDA). Se pretreatment compensated deficits in the sperm parameters (concentration, motility and morphology) induced by Cd. Se (0.4 mg/kg BW) treatment significantly increased serum testosterone level that was reduced by Cd (on 15th, 25th and 35th day) (P<0.01). Se treatment ameliorated Cd-induced reduction in testicular steroidogenic acute regulatory (StAR) and 17ß-hydroxysteroid dehydrogenase (17ß-HSD) activities. The present study suggest that the protective potential of Se against Cd-induced reprotoxicity might be due to up-regulation StAR and testosterone synthetic enzyme activity, which could be useful for increasing testosterone synthesis for achieving optimum protection in sperm quality and spermatogenesis.

Liquiritigenin inhibits tumor growth and vascularization in a mouse model of HeLa cells.

Angiogenesis is one of the crucial steps in the transition of a tumor from a small, harmless cluster of mutated cells to a large, malignant growth, capable of spreading to other organs throughout the body. Vascular endothelial growth factor (VEGF) that stimulates vasculogenesis and angiogenesis is thought to be as an anti-angiogenic target for cancer therapy. Liquiritigenin (LQ), a flavanone existing in Radix glycyrrhiza, shows extensive biological activities, such as anti-inflammatory and anti-cancer properties. In our studies, liquiritigenin effectively inhibited the growth of tumors xenografted in nude mice from human cervical cancer cell line HeLa cells, and microvascular density (MVD) of the tumor exposed to liquiritigenin was reduced in a dose dependent manner, especially in the high dose group. Moreover, the expression and secretion of VEGF were down-regulated by the drug in vivo and in vitro. Therefore, liquiritigenin can be further studied on cancer and other diseases associated with VEGF up-regulation.

Inhibitory effect of liquiritigenin on migration via downregulation proMMP-2 and PI3K/Akt signaling pathway in human lung adenocarcinoma A549 cells.

Liquiritigenin (LQ) is a flavanone extracted from Glycyrrhizae, which has multiple biological effects, such as antiinflammation and anticancer. This study is the first to investigate the effect of LQ on the migration of human lung adenocarcinoma A549 cells in vitro. First, LQ exhibited inhibitory effects on the adhesion and migration of A549 cells in the absence of cytotoxicity. Gelatin zymography and Western blot analysis showed that LQ significantly reduced the expression of promatrix metalloproteinase-2 (proMMP-2) in A549 cells in terms of both activity and protein level. Second, LQ inhibited the phosphorylation of Akt and activated the phosphorylation of extracellular signal-regulated kinase 1 and 2 (ERK1/2). Furthermore, the treatment of inhibitors specific for Akt (LY294002) and ERK1/2 (U0126) to A549 cells resulted in reduced activity of proMMP-2. These results suggested that the inhibition on proMMP-2 expression by LQ may be through suppression on PI3K/Akt signaling pathway, which in turn led to the inhibition of lung adenocarcinoma A549 cells migration. However, activation of ERK might not be involved in the regulation of proMMP-2. Taken together, LQ may be considered as a potential interfering agent of cancer progression.