Involvement of p38 Activation and Mitochondria in Death of Human Leukemia Cells Induced by an Agonistic Human Monoclonal Antibody Fab Specific to TRAIL Receptor 1.

The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces cancer cell death with minimal damage to normal cells; however, some cancer cells are resistant to TRAIL. TRAIL resistance may be overcome by agonistic antibodies to TRAIL receptors. In this study, we report the toxic effects of a novel recombinant agonistic human anti-TRAIL receptor 1 (DR4) monoclonal antibody Fab fragment, DR4-4, on various TRAIL-resistant and -sensitive cancer cell lines. The mechanisms of DR4-4 Fab-induced cell death in a human T cell leukemia cell line (Jurkat) were investigated using cell viability testing, immunoblotting, immunoassays, flow cytometry, and morphological observation. DR4-4 Fab-induced caspase-independent necrosis was observed to occur in Jurkat cells in association with p38 mitogen-activated protein kinase activation, cellular FLICE (FADD-like IL-1ß-converting enzyme)-inhibitory protein degradation, decreased mitochondrial membrane potential, and increased mitochondrial reactive oxygen species production. Increased cytotoxic effects of DR4-4 Fab were observed in combination with TRAIL or γ-irradiation. Our results indicate that the novel DR4-4 Fab might overcome TRAIL-resistance and induce death in leukemia cells via cellular mechanisms different from those activated by TRAIL. DR4-4 Fab may have application as a potential therapeutic antibody fragment in single or combination therapy for cancer.

Korean Guidelines for Pharmacoeconomic Evaluations: Updates in the Third Version.

The first version of the pharmacoeconomic (PE) guidelines was published in South Korea in 2006. Despite its first revision in 2011, there were still ambiguities in its interpretation. Moreover, methodologies for estimating effectiveness and costs have also evolved since then. Under these circumstances, the Health Insurance Review and Assessment Service published the third version in January 2021. This article reviews the revision process and major changes made in the new edition of the PE guidelines. The revision was processed through reviews of the previous 50 PE submissions, international guidelines, academic literature, and surveys and advisory meetings to obtain stakeholders' opinions. The analysis perspective has changed from a limited societal perspective to a healthcare system perspective. In addition to the drug with the highest market share, drugs used in clinical trials can be selected as comparators under certain conditions. The discount rate decreased from 5% to 4.5%. Furthermore, the revised guidelines provide more detailed and specific instructions for items including non-inferiority margin, extrapolation, utility elicitation, and uncertainty. Treatment switch and co-dependent technology guidelines are newly included; the budget impact analysis guideline is deleted. Through this revision, transparency and consistency of decision-making is expected to improve.

Validating diverse human body models against side impact tests with post-mortem human subjects.

This study aimed at evaluating the ability of morphed finite element (FE) human body models (HBMs) to reproduce the impact responses of post-mortem human subjects (PMHS) with various stature and shape. Ten side impact tests previously performed using seven PMHS under 3 m/s and 8 m/s impact velocities were selected for model evaluation. With weight, stature, sex, and age of PMHS, seven FE HBMs were developed by morphing the midsize male THUMS model into the target geometries predicted by the statistical skeleton and external body shape models. The model-predicted force histories, accelerations along the spine, and deflections in the chest and abdomen were compared to the test data. For comparison, simulations in all testing conditions were also conducted with the original midsize male THUMS, and the results from the THUMS simulations were scaled to the weight and stature from each PMHS. The CORrelation and Analysis (CORA) was used to evaluate the model accuracy, with CORA scores close to one indicating excellent agreement. Ten simulations using the morphed models exhibited 0.80 ±â€¯0.01, 0.80 ±â€¯0.01, 0.78 ±â€¯0.02, and 0.78 ±â€¯0.02 CORA scores for the impact forces to the thorax, abdomen, iliac-wings, and greater-trochanter, respectively; the corresponding CORA scores with the original THUMS were markedly lower at 0.60 ±â€¯0.06, 0.69 ±â€¯0.05, 0.71 ±â€¯0.05, and 0.69 ±â€¯0.04; while those for the scaled THUMS were 0.65 ±â€¯0.05, 0.71 ±â€¯0.05, 0.73 ±â€¯0.05, and 0.72 ±â€¯0.02, also lower than the morphed models. Across all simulations, the morphed HBMs demonstrated significantly higher accuracy than the THUMS with or without scaling. These results suggested the necessity of accounting for size and shape effects on predicting human responses in side impacts.

Identification of circulating tumor cells with EML4-ALK translocation using fluorescence in situ hybridization in advanced ALK-positive patients with lung cancer.

[This retracts the article DOI: 10.3892/ol.2018.8480.].

Cordycepin induces apoptosis in human bladder cancer T24 cells through ROS-dependent inhibition of the PI3K/Akt signaling pathway.

Cordycepin, a derivative of nucleoside adenosine, is one of the active ingredients extracted from the fungi of genus Cordyceps, which have been used for traditional herbal remedies. In this study, we examined the effect of cordycepin on the proliferation and apoptosis of human bladder cancer T24 cells and its mechanism of action. Cordycepin treatment significantly reduced the cell survival rate of T24 cells in a concentration-dependent manner, which was associated with the induction of apoptosis. Cordycepin activated caspase-8 and -9, which are involved in the initiation of extrinsic and intrinsic apoptosis pathways, respectively, and also increased caspase-3 activity, a typical effect caspase, subsequently leading to poly (ADP-ribose) polymerase cleavage. Additionally, cordycepin increased the Bax/Bcl-2 ratio and truncation of Bid, and destroyed the integrity of mitochondria, which contributed to the cytosolic release of cytochrome c. Moreover, cordycepin effectively inactivated the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway, while LY294002, a PI3K/Akt inhibitor, increased the apoptosis-inducing effect of cordycepin. Cordycepin further enhanced the intracellular levels of reactive oxygen species (ROS), while the addition of N-acetyl cysteine (NAC), a ROS inhibitor, significantly diminished cordycepin-induced mitochondrial dysfunction and growth inhibition, and also blocked the inactivation of PI3K/Akt signaling pathway. Furthermore, the presence of NAC significantly attenuated the enhanced apoptotic cell death and reduction of cell viability by treatment with cordycepin and LY294002. Collectively, the data indicate that cordycepin induces apoptosis through the activation of extrinsic and intrinsic apoptosis pathways and the ROS-dependent inactivation of PI3K/Akt signaling in human bladder cancer T24 cells.

Measuring rib cortical bone thickness and cross section from CT.

This study assesses the ability to measure local cortical bone thickness, and to obtain mechanically relevant properties of rib cross-sections from clinical-resolution computed tomography (CT) scans of human ribs. The study utilized thirty-four sections of ribs published by Perz et al. (2015) in three modalities: standard clinical CT (clinCT), high-resolution clinical CT (HRclinCT), and microCT (µCT). Clinical-resolution images were processed using a Cortical Bone Mapping (CBM) algorithm applied to cross-cortex signals resampled perpendicularly to an initial smooth periosteal border. Geometric constraints were applied to remove outlier signals from consideration, and final predicted periosteal and endosteal borders from HRclinCT and clinCT were developed. Target values for local cortical thickness and for overall cross-sectional area and inertial properties were obtained from segmentation of the periosteal and endosteal borders on each corresponding µCT image. Errors in prediction (mean ±â€¯SD) of local cortical bone thickness for HRclinCT and clinCT resolutions were -0.03±0.17 mm and -0.05±0.22 mm, respectively, with R2 coefficients of determination from linear regression of 0.82 and 0.71 (p < 0.0001 for both). Predicted cortical shell measures derived from the periosteal and endosteal borders included total cross-sectional area (prediction errors of 6 ±â€¯3% and -1±5% respectively for HRclinCT and clinCT with R2 correlations of 0.99 and 0.96), cortical shell area (errors of -3±8% and -8±11% with R2 correlations of 0.91 and 0.87), and principal area moment of inertia (errors of 2 ±â€¯8% and -3±11% with R2 correlations of 0.98 and 0.95). Results here show substantial reductions in rib cross-sectional measurement error compared to past histogram-based thresholding methods and provide first validation of the CBM method when applied to rib bones. With the ubiquity of clinical CT scans covering the thorax and ribs, this study opens the door for individualized and population-wide quantification of rib structural properties and their corresponding effects on rib injury.

ABT-737 ameliorates docetaxel resistance in triple negative breast cancer cell line.

PURPOSE: This study aimed to validate the synergistic effect of ABT-737 on docetaxel using MDA-MB-231, a triple negative breast cancer (TNBC) cell line overexpressing B-cell lymphoma-2 (Bcl-2). METHODS: Western blot analysis was performed to assess expression levels of Bcl-2 family proteins and caspase-related molecules. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle distribution was determined by flow cytometry analysis. Benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (z-VAD-fmk) was used for pretreatment to assess the role of caspases. RESULTS: Cell viability of MDA-MB-231 after combination treatment with ABT-737 and docetaxel was significantly lower than that after docetaxel or ABT-737 monotherapy based on MTT assay (both P < 0.001), with a combination index of 0.41. The proportion of sub-G1 population after combination treatment was significantly higher than that after docetaxel or ABT-737 monotherapy (P = 0.001, P = 0.003, respectively). Pretreatment with z-VAD-fmk completely restored cell viability of MDA-MB-231 from apoptotic cell death induced by combination therapy (P = 0.001). Although pro-caspase-8 or Bid did not show significant change in expression level, pro-casepase-9 showed significantly decreased expression after combination treatment. Cleaved caspase-3 showed increased expression while poly (ADP-ribose) polymerase cleavage was induced after combination treatment. However, hypoxia-inducible factor 1-alpha and aldehyde dehydrogenase 1 totally lost their expression after combination treatment. CONCLUSION: Combination of ABT-737 with docetaxel elicits synergistic therapeutic effect on MDA-MB-231, a TNBC cell line overexpressing Bcl-2, mainly by activating the intrinsic pathway of apoptosis. Therefore, adjunct of ABT-737 to docetaxel might be a new therapeutic option to overcome docetaxel resistance of TNBCs overexpressing Bcl-2.

Thoracolumbar Spine Fracture occurring in Obese People involved in Motor Vehicle Crashes.

Crash data from the International Center of Automotive Medicine (ICAM) database, with analytic morphomics, were used to evaluate thoracolumbar spine fractures for obese occupants in frontal crashes. Two BMI (Body Mass Index) groups (non-obese and obese) with a maximum abbreviated injury scale (MAIS) in the spine region of ≥2 (MAIS_6S 2+) were categorised and compared. The fracture types were assessed based on AIS for each occupant. Univariate analyses were conducted to investigate the association between analytic morphomics measures and thoracolumbar spine fracture. The results indicate that MAIS 2+ injury occurred mainly in severe crashes with high delta-V and large intrusion. Transverse process fractures were the most common AIS 2+ fractures, followed by minor compression type fractures (≤ 20% anterior height). Compared to the non-obese occupants, the majority of obese occupants sustained transverse process fractures at lumbar vertebra with a higher incidence ratio. A statistical analysis was conducted, using vehicle, demographic, and morphomic variables, to explain the difference between transverse process fractures and vertebra body compression fractures. Transverse process fractures were related to BMI and vehicle factors (intrusion) in the obese group. In addition, morphomics related to fat distribution, muscle area, and cortical bone density are the major difference between non-obese and obese occupants.

Identification of circulating tumor cells with EML4-ALK translocation using fluorescence in situ hybridization in advanced ALK-positive patients with lung cancer.

Analysis of anaplastic lymphoma kinase (ALK) rearrangement in non-small cell lung cancer (NSCLC) is considered to be a useful tool when considering predictive biomarker detection for evaluating eligibility for targeted therapy. It is not always possible to perform a tumor biopsy in patients. Isolation and culturing of circulating tumor cells (CTCs) may be an alternative to tumor biopsies for the diagnosis of ALK rearrangement. Blood was collected from 22 patients with NSCLC harboring ALK rearrangement and was divided into two groups: One for immunofluorescence staining and the other for culture. Samples were filtered by size and cultured CTCs were analyzed for echinoderm microtubule-associated protein-like 4-ALK translocation using fluorescence in situ hybridization. CTCs positive for epithelial cell adhesion molecule and CTCs exhibiting ALK rearrangement were detected. Therefore, CTCs may be used as a potential alternative method to tissue biopsy for diagnosing ALK rearrangement. Additionally, this method may have clinical applications including serial blood sampling for the development of personalized cancer therapy based on individual genomic information.

Breast and Cervical Cancer Screening Behavior in Female Cancer Survivors: The Korea National Health and Nutrition Examination Survey, 2007-2012.

BACKGROUND: The aim of this study was to compare breast and cervical cancer screening rates between female cancer survivors and a population without cancer to identify factors related to cervical and breast cancer screening in cancer survivors. METHODS: We included 17,765 adults (738 cancer survivors and 17,027 individuals without cancer) in this study, all of whom who were 30 years of age or older and participated in the Fourth and Fifth Korean National Health and Nutritional Examination Surveys from 2007-2012. Multiple logistic regression analysis was performed to identify factors related to cervical and breast cancer screening uptake in female cancer survivors. RESULTS: The screening rate for breast cancer was 56.6%, which was higher than that in the non-cancer control group (P=0.001). The screening rate for cervical cancer was 51.4%, which was not different from that of the non-cancer control group. In terms of breast cancer screening, cancer survivors showed no significant difference in the rate of screening 5 years after their cancer diagnosis. However, cervical cancer survivors were less likely to have cervical cancer screening 10 years after their cancer diagnosis. There was no significant association between cancer screening and sociodemographic factors. CONCLUSION: Breast and cervical cancer screening rates in Korean female cancer survivors are low. Secondary primary cancer screening of female cancer survivors needs to be planned in a comprehensive manner, with the consideration of influences beyond sociodemographic factors.

Impact Response Comparison Between Parametric Human Models and Postmortem Human Subjects with a Wide Range of Obesity Levels.

OBJECTIVE: Field data analyses have shown that obesity significantly increases the occupant injury risks in motor vehicle crashes, but the injury assessment tools for people with obesity are largely lacking. The objectives of this study were to use a mesh morphing method to rapidly generate parametric finite element models with a wide range of obesity levels and to evaluate their biofidelity against impact tests using postmortem human subjects (PMHS). METHODS: Frontal crash tests using three PMHS seated in a vehicle rear seat compartment with body mass index (BMI) from 24 to 40 kg/m2 were selected. To develop the human models matching the PMHS geometry, statistical models of external body shape, rib cage, pelvis, and femur were applied to predict the target geometry using age, sex, stature, and BMI. A mesh morphing method based on radial basis functions was used to rapidly morph a baseline human model into the target geometry. The model-predicted body excursions and injury measures were compared to the PMHS tests. RESULTS: Comparisons of occupant kinematics and injury measures between the tests and simulations showed reasonable correlations across the wide range of BMI levels. CONCLUSIONS: The parametric human models have the capability to account for the obesity effects on the occupant impact responses and injury risks.

Cancer gene panel analysis of cultured circulating tumor cells and primary tumor tissue from patients with breast cancer.

Although numerous effective therapies have improved the survival rate of patients with breast cancer, a number of patients present with tumor recurrence and metastasis. A liquid biopsy of circulating tumor cells (CTC) is a non-invasive method to obtain tumor cells and may be used as substitute for a tumor tissue biopsy. The present study focuses on determining whether CTC culture is an optimal method of obtaining sufficient amounts of CTCs for molecular analysis. The current study demonstrates a method of isolating and culturing CTCs from patients with breast cancer and the construction of a molecular profile of cultured cells using the Ion AmpliSeq Cancer Gene Panel V2. Gene mutations that were observed in cultured CTCs were compared with those observed in primary tumor tissues. CTCs were isolated and cultured from the blood of six patients with breast cancer. Mutations from the Catalogue Of Somatic Mutation In Cancer (COSMIC) were detected in Platelet-Derived Growth Factor Receptor Alpha, MET (also known as Hepatocyte Growth Factor Receptor), Phosphatase and Tensin Homolog, Harvey Rat Sarcoma Viral Oncogene Homolog, SWI/SNF Related, Matrix Associated, Actin Dependent Regulator of Chromatin Subfamily B Member 1, Cyclin Dependent Kinase Inhibitor 2A and MutL Homolog 1 genes in 5/6 samples. A comparison between mutations detected in cultured CTCs and mutations detected in primary tumor tissues demonstrated that a large number of mutations that were identified in CTCs were also detected in primary tumor tissues. The results from the current study describe a novel cell culture approach that may be used to obtain an optimal number of CTCs for molecular analysis. This novel approach is able to be used as a tool for liquid biopsy during breast cancer treatment.

Development, Evaluation, and Sensitivity Analysis of Parametric Finite Element Whole-Body Human Models in Side Impacts.

Occupant stature and body shape may have significant effects on injury risks in motor vehicle crashes, but the current finite element (FE) human body models (HBMs) only represent occupants with a few sizes and shapes. Our recent studies have demonstrated that, by using a mesh morphing method, parametric FE HBMs can be rapidly developed for representing a diverse population. However, the biofidelity of those models across a wide range of human attributes has not been established. Therefore, the objectives of this study are 1) to evaluate the accuracy of HBMs considering subject-specific geometry information, and 2) to apply the parametric HBMs in a sensitivity analysis for identifying the specific parameters affecting body responses in side impact conditions. Four side-impact tests with two male post-mortem human subjects (PMHSs) were selected to evaluate the accuracy of the geometry and impact responses of the morphed HBMs. For each PMHS test, three HBMs were simulated to compare with the test results: the original Total Human Model for Safety (THUMS) v4.01 (O-THUMS), a parametric THUMS (P-THUMS), and a subject-specific THUMS (S-THUMS). The P-THUMS geometry was predicted from only age, sex, stature, and BMI using our statistical geometry models of skeleton and body shape, while the S-THUMS geometry was based on each PMHS's CT data. The simulation results showed a preliminary trend that the correlations between the PTHUMS- predicted impact responses and the four PMHS tests (mean-CORA: 0.84, 0.78, 0.69, 0.70) were better than those between the O-THUMS and the normalized PMHS responses (mean-CORA: 0.74, 0.72, 0.55, 0.63), while they are similar to the correlations between S-THUMS and the PMHS tests (mean-CORA: 0.85, 0.85, 0.67, 0.72). The sensitivity analysis using the PTHUMS showed that, in side impact conditions, the HBM skeleton and body shape geometries as well as the body posture were more important in modeling the occupant impact responses than the bone and soft tissue material properties and the padding stiffness with the given parameter ranges. More investigations are needed to further support these findings.

Effects of biceps tension on the torn superior glenoid labrum.

The purpose of this study was to evaluate the role of the tension on the long head of the biceps tendon in the propagation of SLAP tears by studying the mechanical behavior of the torn superior glenoid labrum. A previously validated finite element model was extended to include a glenoid labrum with type II SLAP tears of three different sizes. The strain distribution within the torn labral tissue with loading applied to the biceps tendon was investigated and compared to the inact and unloaded conditions. The anterior and posterior edges of each SLAP tear experienced the highest strain in the labrum. Labral strain increased with increasing biceps tension. This effect was stronger in the labrum when the size of the tear exceeded the width of the biceps anchor on the superior labrum. Thus, this study indicates that biceps tension influences the propagation of a SLAP tear more than it does the initiation of a tear. Additionally, it also suggests that the tear size greater than the biceps anchor site as a criterion in determining optimal treatment of a type II SLAP tear.

Development and Validation of an Older Occupant Finite Element Model of a Mid-Sized Male for Investigation of Age-related Injury Risk.

The aging population is a growing concern as the increased fragility and frailty of the elderly results in an elevated incidence of injury as well as an increased risk of mortality and morbidity. To assess elderly injury risk, age-specific computational models can be developed to directly calculate biomechanical metrics for injury. The first objective was to develop an older occupant Global Human Body Models Consortium (GHBMC) average male model (M50) representative of a 65 year old (YO) and to perform regional validation tests to investigate predicted fractures and injury severity with age. Development of the GHBMC M50 65 YO model involved implementing geometric, cortical thickness, and material property changes with age. Regional validation tests included a chest impact, a lateral impact, a shoulder impact, a thoracoabdominal impact, an abdominal bar impact, a pelvic impact, and a lateral sled test. The second objective was to investigate age-related injury risks by performing a frontal US NCAP simulation test with the GHBMC M50 65 YO and the GHBMC M50 v4.2 models. Simulation results were compared to the GHBMC M50 v4.2 to evaluate the effect of age on occupant response and risk for head injury, neck injury, thoracic injury, and lower extremity injury. Overall, the GHBMC M50 65 YO model predicted higher probabilities of AIS 3+ injury for the head and thorax.

Shoulder labral pathomechanics with rotator cuff tears.

Rotator cuff tears (RCTs), the most common injury of the shoulder, are often accompanied by tears in the superior glenoid labrum. We evaluated whether superior humeral head (HH) motion secondary to RCTs and loading of the long head of the biceps tendon (LHBT) are implicated in the development of this associated superior labral pathology. Additionally, we determined the efficacy of a finite element model (FEM) for predicting the mechanics of the labrum. The HH was oriented at 30° of glenohumeral abduction and neutral rotation with 50N compressive force. Loads of 0N or 22N were applied to the LHBT. The HH was translated superiorly by 5mm to simulate superior instability caused by RCTs. Superior displacement of the labrum was affected by translation of the HH (P<0.0001), position along the labrum (P<0.0001), and interaction between the location on the labrum and LHBT tension (P<0.05). The displacements predicted by the FEM were compared with mechanical tests from 6 cadaveric specimens and all were within 1 SD of the mean. A hyperelastic constitutive law for the labrum was a better predictor of labral behavior than the elastic law and insensitive to ±1 SD variations in material properties. Peak strains were observed at the glenoid-labrum interface below the LHBT attachment consistent with the common location of labral pathology. These results suggest that pathomechanics of the shoulder secondary to RCTs (e.g., superior HH translation) and LHBT loading play significant roles in the pathologic changes seen in the superior labrum.

Effects of biceps tension and superior humeral head translation on the glenoid labrum.

We sought to understand the effects of superior humeral head translation and load of the long head of biceps on the pathomechanics of the superior glenoid labrum by predicting labral strain. Using micro-CT cadaver images, a finite element model of the glenohumeral joint was generated, consisting of humerus, glenoid bone, cartilages, labrum, and biceps tendon. A glenohumeral compression of 50 N and biceps tensions of 0, 22, 55, and 88 N were applied. The humeral head was superiorly translated from 0 to 5 mm in 1-mm increments. The highest labral strain occurred at the interface with the glenoid cartilage and bone beneath the origin of the biceps tendon. The maximum strain was lower than the reported failure strain. The humeral head motion had relatively greater effect than biceps tension on the increasing labral strain. This supports the mechanistic hypothesis that superior labral lesions result mainly from superior migration of the humeral head, but also from biceps tension

Characterization of human anti-heat shock protein 60 monoclonal autoantibody Fab fragments in atherosclerosis: genetic and functional analysis.

Heat shock protein 60 (HSP60) is an important autoantigen in atherosclerosis. The genetic structures and pathogenic roles of anti-HSP60 autoantibodies, however, have not been well elucidated. Here, we cloned nine monoclonal IgG Fabs against human HSP60 from peripheral blood lymphocytes of atherosclerosis patients. Analysis of the variable region sequences revealed that the antibodies used diverse members of V(H) gene families with different D(H) and J(H) segments. However, in V(L), KV3-20 gene family member along with KJ1 segment was used often. Similarities between the rearranged genes and the closest germline sequences were low. The sequences of V(H) were highly mutated and V(H)-CDR3 varied greatly in length and sequences. The ratios of R/S (replacement mutation to silent mutation) were remarkably high in CDRs in all V(H) regions except one clone. Furthermore, mutations to positively charged amino acids were frequent in all V(H) and most V(L). These results suggest that the occurrence of somatic hypermutation and antigenic selection is critical, not the usage of certain V(H) gene family members or segments, in producing affinity-matured anti-HSP60 autoantibodies in atherosclerosis. However, expression of the combined germline genes of KV3-20 with KJ1 might be important for the selection by HSP60 at the early stage of B cell development. Two of these anti-HSP60 Fabs inhibited the binding and uptake of human HSP60 by murine macrophage cells. One of them also reduced the release of the pro-inflammatory mediators and inhibited the activation of NF-κB in HSP60-stimulated macrophages. To elucidate the functional roles of anti-HSP60 autoantibodies in atherosclerosis and the potential use of these Fabs to treat atherosclerosis, further investigation is worthy to be performed.

Chlorella methanol extract reduces lipid accumulation in and increases the number of apoptotic 3T3-L1 cells.

Obesity is a fast-growing problem that is reaching pandemic proportions. Chlorella has many biological merits for promoting health, including detoxification, boosting the immune system, and even reversing cancer. In this study, we found that methanol extract of Chlorella reduces lipid accumulation in 3T3-L1 adipocytes. It has been postulated that these antiobesity effects could be a result of reducing adipogenesis. First, the MTT assay indicated that Chlorella significantly inhibited cell growth of 3T3-L1 preadipocytes. The accumulation of triacylglycerol in 3T3-L1 adipocytes decreased in cells treated with Chlorella versus those in untreated cells by Oil Red O staining. In parallel, Chlorella showed a significant dose-dependent increase in lactate dehydrogenase activity in culture medium of differentiated 3T3-L1 adipocytes. Second, we investigated the effects of Chlorella on the induction of apoptosis by fluorescence-activated cell sorting analysis. Chlorella showed that apoptotic cells increased in a time- and dose-dependent manner in cell apoptosis analysis by propidium iodide (PI) staining. Treatment with Chlorella decreased the number of normal cells and increased the number of apoptotic cells in a dose-dependent manner in annexin V-fluorescein isothiocyanate/PI double staining. Therefore, Chlorella is expected to efficiently reduce adipogenesis in 3T3-L1 adipocytes and to induce apoptosis in 3T3-L1 preadipocytes.