Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

Katia Maalouf1, Elias Baydoun2, Sandra Rizk11Department of Natural Sciences, Lebanese American University, Beirut, Lebanon; 2Department of Biology, American University of Beirut, Beirut, LebanonBackground: Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer.Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes.Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry.Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 µg/µL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF- β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines.Conclusion: In conclusion, kefir is effective in inhibiting proliferation and inducing apoptosis of HTLV-1-negative malignant T-lymphocytes. Therefore, further in vivo investigation is highly recommended.Keywords: apoptosis, cancer, CEM, Jurkat, kefir, leukemi

Biosynthesis and assembly of pectin and glucuronoarabinoxylan in plants

Nascent pectin and glucuronarabinoxylan (GAX), synthesized in vitro by membrane-bound enzymes from etiolated pea (Pisum sativum L.) epicotyls, were found to bind to pea xyloglucan in a pH-dependent manner. The binding was maximum at low pH (3-4), and decreased to almost zero at pH 6. The binding seemed to occur instantaneously, to be non-covalent, and to require both terminal fucose residues of xyloglucan, in addition to the non-reduced acid residues of GAX and pectin. Removal by protease of the proteins attached to nascent pectin and GAX, greatly reduced the maximum binding and abolished the pH-dependence. The proteins involved seem to have approximate molecular weights of 14 and 94 kDa. The pH-dependent binding of nascent pectin and GAX is not completely specific to xyloglucan, since some binding occurred to a range of other matrix polysaccharides, though at a lower level than to pea xyloglucan. Newly-deposited pectin was extracted from peas that were incubated with radioactively labelled sucrose. It was shown to behave in a similar manner as nascent pectin, exhibiting the same pH-dependent binding pattern to xyloglucan. Protease treatment of pectin decreased the binding, indicating the possible presence of proteins attached to pectin in the cell wall, and revealing the role of those proteins in the interaction of pectin with other matrix polysaccharides, particularly xyloglucan. The pH-dependence of the binding suggests a functional interaction with the mechanisms that control growth, since the wall pH decreases when elongation growth is initiated. The proteins involved would play a significant role in cell-wall assembly and cell-wall elongation

Eating habits and obesity among Lebanese university students

<p>Abstract</p> <p>Background</p> <p>In the past year Lebanon has been experiencing a nutritional transition in food choices from the typical Mediterranean diet to the fast food pattern. As a consequence, the dietary habits of young adults have been affected; thus, overweight and obesity are increasingly being observed among the young. The purpose of this study is to assess the prevalence of overweight and obesity on a sample of students from the Lebanese American University (in Beirut) and to examine their eating habits.</p> <p>Methods</p> <p>A cross-sectional survey of 220 students (43.6% male and 56.4% female), aged 20 ± 1.9 years, were chosen randomly from the Lebanese American University (LAU) campus during the fall 2006 semester. Students were asked to fill out a self-reported questionnaire that included questions on their eating, drinking and smoking habits. Also, their weight, height, percentage body fat and body mass index were measured. Body mass index (BMI) was used to assess students' weight status. Statistical analyses were performed using the Statistical Package for Social Sciences software (version 13.0) to determine overweight and obesity among students and to categorize eating habits.</p> <p>Results</p> <p>This study showed that the majority of the students (64.7%) were of normal weight (49% male students compared to 76.8% female students). The prevalence of overweight and obesity was more common among male students compared to females (37.5% and 12.5% vs. 13.6% and 3.2%, respectively). In contrast, 6.4% female students were underweight as compared to 1% males. Eating habits of the students showed that the majority (61.4%) reported taking meals regularly. Female students showed healthier eating habits compared to male students in terms of daily breakfast intake and meal frequency. 53.3% of female students reported eating breakfast daily or three to four times per week compared to 52.1% of male students. There was a significant gender difference in the frequency of meal intake (P = 0.001). Intake of colored vegetables and fruits was common among students. A total of 30.5% reported daily intake of colored vegetables with no gender differences (31.5% females vs. 29.2% males). Alcohol intake and smoking were not common among students.</p> <p>Conclusion</p> <p>In spite of the overall low prevalence of overweight and obesity in the studied sample, results indicate that university students would possibly benefit from a nutrition and health promotion program to reduce the tendency of overweight and obesity, especially among male students, and to improve students' eating habits.</p

Dieting practices and body image perception among Lebanese university students

Dieting is becoming a popular phenomenon among university students to achieve or maintain a healthy weight. The purpose of this study is to obtain a preliminary understanding of what dieting practices university students use in order to achieve their desirable body weight and to determine the magnitude of body dissatisfaction in relation to weight status among a sample of students (n=252) from the Lebanese American University in Beirut, Lebanon. Students filled out a self-reported questionnaire that included questions on their dieting and physical activity practices in addition to the body shape questionnaire (BSQ). Weight and height were measured to calculate body mass index. Percentage body fat was measured using Tanita scale body fat analyzer 300A. The outcome of this study showed that smoking and unhealthy dieting practices were not common among students (only 26% reported smoking, 8% reported taking laxatives and 4% taking diet pills). Half of the students reported practicing regular physical activity. Multivitamin intake was also not popular among students. BSQ scores indicate that the majority of students were not worried about their body image perception (64% reported not being worried, 19% were slightly worried, 12% were moderately worried and 5% were extremely worried). A gender difference was observed in the BSQ scores, as 89% of the &quot;extremely worried&quot; students were females. Collectively, results indicate that unhealthy dieting practices are uncommon among students. However, developing health promotion awareness&apos; programs to promote good self image within the concept of a realistic healthy weight will be beneficial, especially among females

RNA buffers the phase separation behavior of prion-like RNA binding proteins

Prion-like RNA binding proteins (RBPs) such as TDP43 and FUS are largely soluble in the nucleus but form solid pathological aggregates when mislocalized to the cytoplasm. What keeps these proteins soluble in the nucleus and promotes aggregation in the cytoplasm is still unknown. We report here that RNAcritically regulates the phase behavior of prion-like RBPs. Low RNA/protein ratios promote phase separation into liquid droplets, whereas high ratios prevent droplet formation in vitro. Reduction of nuclear RNA levels or genetic ablation of RNA binding causes excessive phase separation and the formation of cytotoxic solid-like assemblies in cells. We propose that the nucleus is a buffered system in which high RNA concentrations keep RBPs soluble. Changes in RNA levels or RNA binding abilities of RBPs cause aberrant phase transitions.1125sciescopu

Validation of Melanoma Immune Profile (MIP), a Prognostic Immune Gene Prediction Score for Stage II–III Melanoma

Purpose: Biomarkers are needed to stratify patients with stage II–III melanoma for clinical trials of adjuvant therapy because, while immunotherapy is protective, it also confers the risk of severe toxicity. We previously defined and validated a 53-immune gene melanoma immune profile (MIP) predictive both of distant metastatic recurrence and of disease-specific survival (DSS). Here, we test MIP on a third independent population. Experimental Design: A retrospective cohort of 78 patients with stage II–III primary melanoma was analyzed using the NanoString assay to measure expression of 53 target genes, and MIP score was calculated. Statistical analysis correlating MIP with DSS, overall survival, distant metastatic recurrence, and distant metastasis-free interval was performed using ROC curves, Kaplan–Meier curves, and standard univariable and multivariable Cox proportional hazards models. Results: MIP significantly distinguished patients with distant metastatic recurrence from those without distant metastatic recurrence using ROC curve analysis (AUC = 0.695; P = 0.008). We defined high- and low-risk groups based on the cutoff defined by this ROC curve and find that MIP correlates with both DSS and overall survival by ROC curve analysis (AUC = 0.719; P = 0.004 and AUC = 0.698; P = 0.004, respectively). Univariable Cox regression reveals that a high-risk MIP score correlates with DSS (P = 0.015; HR = 3.2). Conclusions: MIP identifies patients with low risk of death from melanoma and may constitute a clinical tool to stratify patients with stage II–III melanoma for enrollment in clinical trials

Hyperthermia Induces Functional and Molecular Modifications in Cardiac, Smooth and Skeletal Muscle Cells

Comparative Medicine - OneHealth and Comparative Medicine Poster SessionHyperthermia is used for the treatment of a number of diseases, including muscle injuries, inflammations, tendinitis, and osteoarticular disorder. More recently, hyperthermia has been used as an adjuvant in cancer treatment. Only two studies have shown that hyperthermia leads to hypertrophy in in-vitro models of cardiac and skeletal muscle cells. Functional, biochemical and molecular mechanisms of hyperthermia-induced hypertrophy in muscles remain largely undiscovered. We investigated the effects of mild heat shock (HS) on C2C12 skeletal, HL-1 cardiac and AR-75 smooth muscle cells. Mild HS (20 min 43ºC) induced increases in the cell area in all muscle cells tested. C2C12 cells are a well-accepted model of skeletal muscle fibers, and were selected for complementary studies. First, to biochemically confirm an increase in protein synthesis we measured and found an increase of ~6% in total protein content 24 hrs after HS. Second, we examined potential modifications in calcium (Ca) homeostasis regulation by measuring intracellular Ca. We detected a lower resting level of intracellular Ca and smaller and longer caffeine-induced Ca transients in C2C12 muscle cells 24 hrs after HS. Next, to search for molecular mechanisms involved with HS-induced hypertrophy and calcium homeostasis modifications, mRNA from C2C12 muscle cells was analyzed at different time points after HS (0, 1, 2, and 24 hrs). We used an ABI Step One Plus RT2 PCR Array System and a custom-built 96 gene array. We report for the first time that the expression of key heat-shock, hypertrophy/ metabolic, and Ca+2 signaling genes were altered after HS. Hsp70 and Hsp72 genes were highly expressed (211-1829 fold change) after HS. Also, Myh7 (MHC-I), Myh6, Srf, Ppp3r1 and Pck1 were up-regulated by 2-6 fold change compared with control cells.. Furthermore, a reduction in the expression of RyR and Trdn genes was observed (2- 3.6 fold change) with an associated increase in the expression of IP3R genes (2-4 fold change). These results indicate that hyperthermia modulates not only heat-shock related and hypertrophy genes, but also genes involved with metabolism, apoptosis repression, calcium homeostasis and signaling, and cell homeostasis. Our studies offer an initial exploration of the functional, biochemical and molecular mechanisms that may help explain the beneficially adaptive effects of hyperthermia on muscle function. Our studies shall also prove useful for the refinement of a specific device (EM-Stim) to be employed for the treatment of muscle and bone diseases (See poster by Hatem et al). Importantly, our studies have potential translational applications. By learning how to more precisely use hyperthermia to control specific genes that can improve or treat muscle injuries, musculoskeletal, and cardiovascular diseases, the ensuing benefits shall be unmistakable. Our short and long-term goals are: i) optimize our protocols; ii) test HS in animal models; iii) manipulate expression of promising genes of interest in vitro and in in-vivo animal models; iv) initiate clinical studies to fully translate from the bench to the bed-side

Clinical Characteristics and Treatment Patterns of Children and Adults With IgA Nephropathy or IgA Vasculitis: Findings From the CureGN Study

Introduction: The Cure Glomerulonephropathy Network (CureGN) is a 66-center longitudinal observational study of patients with biopsy-confirmed minimal change disease, focal segmental glomerulosclerosis, membranous nephropathy, or IgA nephropathy (IgAN), including IgA vasculitis (IgAV). This study describes the clinical characteristics and treatment patterns in the IgA cohort, including comparisons between IgAN versus IgAV and adult versus pediatric patients. Methods: Patients with a diagnostic kidney biopsy within 5 years of screening were eligible to join CureGN. This is a descriptive analysis of clinical and treatment data collected at the time of enrollment. Results: A total of 667 patients (506 IgAN, 161 IgAV) constitute the IgAN/IgAV cohort (382 adults, 285 children). At biopsy, those with IgAV were younger (13.0 years vs. 29.6 years, P < 0.001), more frequently white (89.7% vs. 78.9%, P = 0.003), had a higher estimated glomerular filtration rate (103.5 vs. 70.6 ml/min per 1.73 m2, P < 0.001), and lower serum albumin (3.4 vs. 3.8 g/dl, P < 0.001) than those with IgAN. Adult and pediatric individuals with IgAV were more likely than those with IgAN to have been treated with immunosuppressive therapy at or prior to enrollment (79.5% vs. 54.0%, P < 0.001). Conclusion: This report highlights clinical differences between IgAV and IgAN and between children and adults with these diagnoses. We identified differences in treatment with immunosuppressive therapies by disease type. This description of baseline characteristics will serve as a foundation for future CureGN studies

Chaperonin Containing T-Complex Polypeptide Subunit Eta (CCT-eta) Is a Specific Regulator of Fibroblast Motility and Contractility

Integumentary wounds in mammalian fetuses heal without scar; this scarless wound healing is intrinsic to fetal tissues and is notable for absence of the contraction seen in postnatal (adult) wounds. The precise molecular signals determining the scarless phenotype remain unclear. We have previously reported that the eta subunit of the chaperonin containing T-complex polypeptide (CCT-eta) is specifically reduced in healing fetal wounds in a rabbit model. In this study, we examine the role of CCT-eta in fibroblast motility and contractility, properties essential to wound healing and scar formation. We demonstrate that CCT-eta (but not CCT-beta) is underexpressed in fetal fibroblasts compared to adult fibroblasts. An in vitro wound healing assay demonstrated that adult fibroblasts showed increased cell migration in response to epidermal growth factor (EGF) and platelet derived growth factor (PDGF) stimulation, whereas fetal fibroblasts were unresponsive. Downregulation of CCT-eta in adult fibroblasts with short inhibitory RNA (siRNA) reduced cellular motility, both basal and growth factor-induced; in contrast, siRNA against CCT-beta had no such effect. Adult fibroblasts were more inherently contractile than fetal fibroblasts by cellular traction force microscopy; this contractility was increased by treatment with EGF and PDGF. CCT-eta siRNA inhibited the PDGF-induction of adult fibroblast contractility, whereas CCT-beta siRNA had no such effect. In each of these instances, the effect of downregulating CCT-eta was to modulate the behavior of adult fibroblasts so as to more closely approximate the characteristics of fetal fibroblasts. We next examined the effect of CCT-eta modulation on alpha-smooth muscle actin (α-SMA) expression, a gene product well known to play a critical role in adult wound healing. Fetal fibroblasts were found to constitutively express less α-SMA than adult cells. Reduction of CCT-eta with siRNA had minimal effect on cellular beta-actin but markedly decreased α-SMA; in contrast, reduction of CCT-beta had minimal effect on either actin isoform. Direct inhibition of α-SMA with siRNA reduced both basal and growth factor-induced fibroblast motility. These results indicate that CCT-eta is a specific regulator of fibroblast motility and contractility and may be a key determinant of the scarless wound healing phenotype by means of its specific regulation of α-SMA expression