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Mitochondria are increasingly recognized to play a role in the airway inflammation of asthma. Model systems to study the role of mitochondrial gene expression in bronchial epithelium are lacking. Here, we create custom bronchial epithelial cell lines that are depleted of mitochondrial DNA. One week of ethidium bromide (EtBr) treatment led to ∼95 % reduction of mtDNA copy number (mtDNA-CN) in cells, which was further reduced by addition of 25 µM 2′,3′-dideoxycytidin (ddC). Treatment for up to three weeks with EtBr and ddC led to near complete loss of mtDNA. The basal oxygen consumption rate (OCR) of mtDNA-depleted BET-1A and BEAS-2B cells dropped to near zero. Glycolysis measured by extracellular acidification rate (ECAR) increased ∼two-fold in cells when mtDNA was eliminated. BET-1A ρ0 and BEAS-2B ρ0 cells were cultured for two months, frozen and thawed, cultured for two more months, and maintained near zero mtDNA-CN. Mitochondrial DNA–depleted BET-1A ρ0 and BEAS-2B ρ0 cell lines are viable, lack the capacity for aerobic respiration, and increase glycolysis. • BET-1A and BEAS-2B cells were treated with ethidium bromide (EtBr) with or without 2′,3′-dideoxycytidine (ddC) to create cells lacking mitochondrial DNA (mtDNA). • Cells’ mtDNA copy number relative to nuclear DNA (nDNA) were verified by quantitative polymerase chain reaction (qPCR). • Cells were also assessed for oxidative phosphorylation by measures of oxygen consumption using the Seahorse analyzer.

Abstract Obesity is a leading cause of preventable death worldwide. Despite this, current strategies for the treatment of obesity remain ineffective at achieving long‐term weight control. This is due, in part, to difficulties in identifying tolerable and efficacious small molecules or biologics capable of regulating systemic nutrient homeostasis. Here, we demonstrate that BAM15, a mitochondrially targeted small molecule protonophore, stimulates energy expenditure and glucose and lipid metabolism to protect against diet‐induced obesity. Exposure to BAM15 in vitro enhanced mitochondrial respiratory kinetics, improved insulin action, and stimulated nutrient uptake by sustained activation of AMPK. C57BL/6J mice treated with BAM15 were resistant to weight gain. Furthermore, BAM15‐treated mice exhibited improved body composition and glycemic control independent of weight loss, effects attributable to drug targeting of lipid‐rich tissues. We provide the first phenotypic characterization and demonstration of pre‐clinical efficacy for BAM15 as a pharmacological approach for the treatment of obesity and related diseases.

Apolipoprotein M (apoM) is a novel apolipoprotein that is reportedly necessary for preβ HDL formation; however, its detailed function remains unknown. We investigated the biogenesis and properties of apoM and its effects on the initial steps of nascent preβ HDL assembly by ABCA1 in HEK293 cells. Transiently transfected apoM was localized primarily in the endomembrane compartment. Pulse-chase analyses demonstrated that apoM is inefficiently secreted, relative to human serum albumin, and that ∼50% remains membrane-associated after extraction with sodium carbonate, pH 11.5. To investigate the role of apoM in nascent preβ HDL formation, ABCA1-expressing or control cells, transfected with empty vector, apoM, or C-terminal epitope-tagged apoM (apoM-C-FLAG), were incubated with 125I-apoA-I for 24 h. Conditioned media were harvested and fractionated by fast-protein liquid chromatography (FPLC) to monitor HDL particle size. Preβ HDL particles were formed effectively in the absence of apoM expression; however, increased apoM expression stimulated the formation of larger-sized nascent preβ HDLs. Immunoprecipitation with anti-apoA-I antibody followed by apoM Western blot analysis revealed that little secreted apoM was physically associated with preβ HDL. Our results suggest that apoM is an atypical secretory protein that is not necessary for ABCA1-dependent preβ HDL formation but does stimulate the formation of larger-sized preβ HDL. We propose that apoM may function catalytically at an intracellular site to transfer lipid onto preβ HDL during or after their formation by ABCA1.

We investigated the in vivo metabolic fate of pre-β HDL particles in human apolipoprotein A-I transgenic (hA-ITg) mice. Pre-β HDL tracers were assembled by incubation of [125I]tyramine cellobiose-labeled apolipoprotein A-I (apoA-I) with HEK293 cells expressing ABCA1. Radiolabeled pre-β HDLs of increasing size (pre-β1, -2, -3, and -4 HDLs) were isolated by fast-protein liquid chromatography and injected into hA-ITg-recipient mice, after which plasma decay, in vivo remodeling, and tissue uptake were monitored. Pre-β2, -3, and -4 had similar plasma die-away rates, whereas pre-β1 HDL was removed 7-fold more rapidly. Radiolabel recovered in liver and kidney 24 h after tracer injection suggested increased (P < 0.001) liver and decreased kidney catabolism as pre-β HDL size increased. In plasma, pre-β1 and -2 were rapidly (

Obesity is associated with low-grade chronic inflammation. We hypothesized that Roux-en-Y gastric bypass (RYGB) surgery would reduce activation of the NLRP3 inflammasome in metabolically active adipose tissue (AT) of obese rats, and this change would be related to decreases in body weight and improved glycemic control.Omental, mesenteric and subcutaneous fat depots were collected from Sprague-Dawley rats: Sham control and RYGB; 90-days after surgery. NLRP3, caspase-1, apoptosis-associated speck-like protein (ASC), IL-1β, IL-18, IL-6 and MCP-1 gene and protein expression were quantified. Glucose metabolism was assessed by oral glucose tolerance test (OGTT).Compared to Sham surgery controls, RYGB surgery decreased IL-6, MCP-1, NLRP3, IL-18, caspase-1 and ASC in omental fat, and decreased IL-6, MCP1, IL-1β, IL-18, caspase-1 and ASC gene expression in mesenteric fat. We observed differential gene expression between visceral and subcutaneous fat for IL-6 and IL-1β, both being downregulated by RYGB in visceral, and upregulated in subcutaneous depots. These changes in gene expression were accompanied by a decrease in NLRP3, ASC, IL-18, caspase-1 and IL-1β protein expression in omental tissue. We found a positive correlation between caspase-1, ASC, MCP-1, IL-18 and IL-6 gene expression following surgery and glucose AUC response in omental fat, while the change in glucose AUC response correlated with caspase-1 gene expression in subcutaneous fat.This study demonstrates that bariatric surgery reverses inflammation in visceral adipose tissue by suppressing NLRP3 inflammasome activation. These are the first data to implicate the NLRP3 inflammasome in diabetes remission after RYGB surgery.

Macrophage infiltration of adipose tissue during weight gain is a central event leading to the metabolic complications of obesity. However, what are the mechanisms attracting professional phagocytes to obese adipose tissue remains poorly understood. Here, we demonstrate that adipocyte-derived microparticles (MPs) are critical "find-me" signals for recruitment of monocytes and macrophages. Supernatants from stressed adipocytes stimulated the attraction of monocyte cells and primary macrophages. The activation of caspase 3 was required for release of these signals. Adipocytes exposed to saturated fatty acids showed marked release of MPs into the supernatant while common genetic mouse models of obesity demonstrate high levels of circulating adipocyte-derived MPs. The release of MPs was highly regulated and dependent on caspase 3 and Rho-associated kinase. Further analysis identified these MPs as a central chemoattractant in vitro and in vivo. In addition, intravenously transplanting circulating MPs from the ob/ob mice lead to activation of monocytes in circulation and adipose tissue of the wild type mice. These data identify adipocyte-derived MPs as novel "find me" signals that contributes to macrophage infiltration associated with obesity.

Patients homozygous for Tangier disease have a near absence of plasma HDL as a result of mutations in ABCA1 and hypercatabolize normal HDL particles. To determine the relationship between ABCA1 expression and HDL catabolism, we investigated intravascular remodeling, plasma clearance, and organ-specific uptake of HDL in mice expressing the human apolipoprotein A-I (apoA-I) transgene in the Abca1 knockout background. Small HDL particles (7.5 nm), radiolabeled with 125I-tyramine cellobiose, were injected into recipient mice to quantify plasma turnover and the organ uptake of tracer. Small HDL tracer was remodeled to 8.2 nm diameter particles within 5 min in human apolipoprotein A-I transgenic (hA-ITg) mice (control) and knockout mice. Decay of tracer from plasma was 1.6-fold more rapid in knockout mice (P < 0.05) and kidney uptake was twice that of controls, with no difference in liver uptake. We also observed 2-fold greater hepatic expression of ABCA1 protein in hA-ITg mice compared with nontransgenic mice, suggesting that overexpression of human apoA-I stabilized hepatic ABCA1 protein in vivo.We conclude that ABCA1 is not required for in vivo remodeling of small HDLs to larger HDL subfractions and that the hypercatabolism of normal HDL particles in knockout mice is attributable to a selective catabolism of HDL apoA-I by the kidney.

This study investigates the buildup of nine Potentially Toxic Elements (PTEs) in agricultural soils, sources of contamination, ecological risks index, and health risks. All samples from four subdistricts contained detectable levels of nine PTEs, with iron, copper, arsenic, cadmium, and lead concentrations surpassing permissible limits. Natural and anthropogenic activities are revealed as the sources of PTEs. The potential ecological risk index of PTEs is very high. The weekly intake of Pb, As, Ni, Mn, Cd, and Fe in children and adults surpassed the safe intake limits. The findings call for a comprehensive environmental protection plan to safeguard public health.

Since its arrival in late November 2022, ChatGPT-3.5 has rapidly gained popularity and significantly impacted how research is planned, conducted, and published using a generative artificial intelligence approach. ChatGPT-4 was released four months later and became more popular in November 2023. However, there is little study about the perception of scientists of these chatbots, especially in soil science. This article presents the new findings of a brief research investigating soil scientists' responses and perceptions towards chatbots in Indonesia. This artificial intelligence application facilitates conversation-based interactions in text format. The study evaluated ten ChatGPT answers to fundamental questions in soil science, which has developed into a normal science with a mutually agreed-upon paradigm. The evaluation was carried out by seven soil scientists recognized for their expertise in Indonesia, using a scale of 1–100. In addition, a questionnaire was distributed to soil scientists at the National Research and Innovation Agency of the Republic of Indonesia (BRIN), universities, and Indonesian Soil Science Society (HITI) members to gauge their perception of ChatGPT's presence in the research field. The study results indicate that the scores of ChatGPT answers range from 82.99 to 92.24. ChatGPT-4 is better than both the paid and free versions of ChatGPT-3.5. There is no significant difference between the English and Indonesian versions of ChatGPT-4.0. However, the perception of general soil scientists about the level of trust is only 55%. Furthermore, 80% of soil scientists believe that chatbots can only be used as digital tools to assist in soil science research and cannot be used without the involvement of soil scientists.

Information on land reserves is crucial and required to support agricultural development in relation to increased population pressure, food demand, and food security. This research aims to identify and evaluate idle abandoned land based on biophysical suitability, status of land concessions, and forest areas to determine potential land reserves for agricultural development to support food security in Indonesia. The results show that, at the national level, the area of suitable abandoned lands for agricultural extensification is 27.7 million ha, but most of these lands have concession permits and are located in forest areas, so 12.4 million ha are still available, with the largest area being in dry land. The identification of abandoned land by employing satellite imagery in 54 districts resulted in a smaller acreage compared to abandoned land being mapped formally at 1:250,000. After considering land ownership and forest status, both sources resulted in similar areas at a scale of 1:50,000 and 1:250,000, i.e., 6.1 million ha and 6.0 million ha, respectively. It seems that land ownership and forest status adjusted the total acreage of identified land reserves at different map scales. An area of around 7.4 million ha will be required to meet food demand in 2045 by assuming constant consumption per capita. We found about 1.7 million ha as potential land reserves, most of which are in conversion or production forests areas. Converting forests or utilizing drylands could be potential alternatives to deal with the lack of land for food production. Moreover, due to limited wetlands, the use of reserve land in that agroecological zone should be in accordance with its designation, comply with the priority principles, and be supported by government regulations and policies, so that food security can be maintained until 2045.

The Indonesian land area is 191.1 million ha, part of which is abandoned land in various agroecosystems that have the potential for expanding the agricultural area. The purpose of this research was to geospatially analyze abandoned land based on its agroecosystem at the national and district levels, as well as to evaluate the land suitability of the land for expanding agricultural development. The methods included: (1) geospatial analysis of the national land cover map at a scale of 1:250,000 combined with soil and climate information to identify abandoned land and examine its agroecosystem, (2) selecting representative districts in each agroecosystem for visual interpretation using high-resolution imagery, i.e., SPOT 6/7, (3) assessing the land suitability of abandoned land for agricultural development at the national and district levels, and (4) predicting national abandoned land and its land suitability. The essential finding is the identification of abandoned land at around 42.6 million ha in Indonesia distributed over six agroecosystems, with the widest being in dry lowland and wet climates. Then, 54 districts were selected to characterize abandoned land by using SPOT 6/7 high-resolution imagery and were interpreted visually. It was found that the abandoned land covered approximately 16.9 million ha. The distribution of abandoned land from the interpretation of satellite imagery was smaller than that of geospatial analysis due to differences in the map scale and the use of ancillary data. The identification of abandoned land from high-resolution imagery should be carried out for all regions of Indonesia to accurately map the distribution of the abandoned land and characterize the properties. However, it requires a large amount of time, cost, and facilities to complete the inventory. The geospatial analysis that combined imageries and ancillary data identified 27.7 million ha of abandoned land suitable for expanding the agricultural area. The largest suitable abandoned land for the purpose was found in the lowlands with a wet climate, especially in Papua, Kalimantan, and Sumatra islands. The identified suitable abandoned land of 54 districts differed by scale, in which it was 11.2 million ha at the scale of 1:250,000 and 8.5 million ha at the scale of 1:50,000, respectively. The potential land expansion for food crops, particularly paddy fields, was only 2.2 million ha, located in mineral swamp land, which was predominantly located in Papua, with inadequate accessibility. Expanding paddy fields for national food security in the future would be constrained by less suitable land resources, while the near future challenge is the competition of land allocation for agricultural and non-agricultural sectors, as well as for food crops and plantations.