Fermented botanical fertilizer controls bacterial wilt of tomatoes caused by Ralstonia pseudosolanacearum.

This study demonstrates the effect of fermented botanical product (FBP) on Ralstonia pseudosolanacearum-induced bacterial wilt disease and unravels its action mechanism. Soaking with diluted FBP solutions (0.1%-0.5%) significantly suppressed bacterial wilt in tomato plants, and FBP-treated tomato plants grew well against R. pseudosolanacearum infection. Growth assays showed that FBP had no antibacterial effect but promoted R. pseudosolanacearum growth. In contrast, few or no R. pseudosolanacearum cells were detected in aerial parts of tomato plants grown in FBP-soaked soil. Subsequent infection assays using the chemotaxis-deficient mutant (ΔcheA) or the root-dip inoculation method revealed that FBP does not affect pathogen migration to plant roots during infection. Moreover, FBP-pretreated tomato plants exhibited reduced bacterial wilt in the absence of FBP. These findings suggest that the plant, but not the pathogen, could be affected by FBP, resulting in an induced resistance against R. pseudosolanacearum, leading to a suppressive effect on bacterial wilt.

Metabolism-linked methylotaxis sensors responsible for plant colonization in Methylobacterium aquaticum strain 22A.

Motile bacteria take a competitive advantage in colonization of plant surfaces to establish beneficial associations that eventually support plant health. Plant exudates serve not only as primary growth substrates for bacteria but also as bacterial chemotaxis attractants. A number of plant-derived compounds and corresponding chemotaxis sensors have been documented, however, the sensors for methanol, one of the major volatile compounds released by plants, have not been identified. Methylobacterium species are ubiquitous plant surface-symbiotic, methylotrophic bacteria. A plant-growth promoting bacterium, M. aquaticum strain 22A exhibits chemotaxis toward methanol (methylotaxis). Its genome encodes 52 methyl-accepting chemotaxis proteins (MCPs), among which we identified three MCPs (methylotaxis proteins, MtpA, MtpB, and MtpC) responsible for methylotaxis. The triple gene mutant of the MCPs exhibited no methylotaxis, slower gathering to plant tissues, and less efficient colonization on plants than the wild type, suggesting that the methylotaxis mediates initiation of plant-Methylobacterium symbiosis and engages in proliferation on plants. To examine how these MCPs are operating methylotaxis, we generated multiple gene knockouts of the MCPs, and Ca2+-dependent MxaFI and lanthanide (Ln3+)-dependent XoxF methanol dehydrogenases (MDHs), whose expression is regulated by the presence of Ln3+. MtpA was found to be a cytosolic sensor that conducts formaldehyde taxis (formtaxis), as well as methylotaxis when MDHs generate formaldehyde. MtpB contained a dCache domain and exhibited differential cellular localization in response to La3+. MtpB expression was induced by La3+, and its activity required XoxF1. MtpC exhibited typical cell pole localization, required MxaFI activity, and was regulated under MxbDM that is also required for MxaF expression. Strain 22A methylotaxis is realized by three independent MCPs, two of which monitor methanol oxidation by Ln3+-regulated MDHs, and one of which monitors the common methanol oxidation product, formaldehyde. We propose that methanol metabolism-linked chemotaxis is the key factor for the efficient colonization of Methylobacterium on plants.

A Novel Mouse Model of Intrahepatic Cholangiocarcinoma Induced by Azoxymethane.

Cholangiocarcinoma is the second most common primary cancer of the liver and has a poor prognosis. Various animal models, including carcinogen-induced and genetically engineered rodent models, have been established to clarify the mechanisms underlying cholangiocarcinoma development. In the present study, we developed a novel mouse model of malignant lesions in the biliary ducts induced by the administration of the carcinogen azoxymethane to obese C57BLKS/J-db/db mice. A histopathological analysis revealed that the biliary tract lesions in the liver appeared to be an intrahepatic cholangiocarcinoma with higher tumor incidence, shorter experimental duration, and a markedly increased incidence in obese mice. Molecular markers analyzed using a microarray and a qPCR indicated that the cancerous lesions originated from the cholangiocytes and developed in the inflamed livers. These findings indicated that this is a novel mouse model of intrahepatic cholangiocarcinoma in the context of steatohepatitis. This model can be used to provide a better understanding of the pathogenic mechanisms of cholangiocarcinoma and to develop novel therapeutic strategies for this malignancy.

Mutations identified in engineered Escherichia coli with a reduced genome.

Characterizing genes that regulate cell growth and survival in model organisms is important for understanding higher organisms. Construction of strains harboring large deletions in the genome can provide insights into the genetic basis of cell growth compared with only studying wild-type strains. We have constructed a series of genome-reduced strains with deletions spanning approximately 38.9% of the E. coli chromosome. Strains were constructed by combining large deletions in chromosomal regions encoding nonessential gene groups. We also isolated strains Δ33b and Δ37c, whose growth was partially restored by adaptive laboratory evolution (ALE). Genome sequencing of nine strains, including those selected following ALE, identified the presence of several Single Nucleotide Variants (SNVs), insertions, deletions, and inversions. In addition to multiple SNVs, two insertions were identified in ALE strain Δ33b. The first was an insertion at the promoter region of pntA, which increased cognate gene expression. The second was an insertion sequence (IS) present in sibE, encoding the antitoxin in a toxin-antitoxin system, which decreased expression of sibE. 5 strains of Δ37c independently isolated following ALE harboring multiple SNVs and genetic rearrangements. Interestingly, a SNV was identified in the promoter region of hcaT in all five strains, which increased hcaT expression and, we predict, rescued the attenuated Δ37b growth. Experiments using defined deletion mutants suggested that hcaT encodes a 3-phenylpropionate transporter protein and is involved in survival during stationary phase under oxidative stress. This study is the first to document accumulation of mutations during construction of genome-reduced strains. Furthermore, isolation and analysis of strains derived from ALE in which the growth defect mediated by large chromosomal deletions was rescued identified novel genes involved in cell survival.

Skeletal muscle atrophy is exacerbated by steatotic and fibrotic liver-derived TNF-α in senescence-accelerated mice.

BACKGROUND AND AIM: Although liver diseases, including non-alcoholic steatohepatitis, are associated with skeletal muscle atrophy, the mechanism behind their association has not been fully elucidated. In this study, the effects of aging and non-alcoholic steatohepatitis on the skeletal muscle, and the interaction between the liver and muscle were investigated using a diet-induced non-alcoholic steatohepatitis model in senescence-accelerated mice. METHODS: A total of four groups of senescence-accelerated mice and the control mice were fed either a non-alcoholic steatohepatitis-inducing or control diet, and their livers and skeletal muscles were removed for examinations. RESULTS: In the senescence-accelerated/non-alcoholic steatohepatitis group, serum level of alanine aminotransferase was markedly elevated and histopathology of non-alcoholic steatohepatitis was significant. Skeletal muscles were also markedly atrophied. The expression of the ubiquitin ligase Murf1 in the muscle was significantly increased with muscle atrophy, while that of Tnfa was not significantly different. In contrast, the hepatic Tnfa expression and serum TNF-α levels were significantly increased in the senescence-accelerated/non-alcoholic steatohepatitis group. These results suggest that liver-derived TNF-α might promote muscle atrophy associated with steatohepatitis and aging through Murf-1. The metabolomic analysis of skeletal muscle indicated higher spermidine and lower tryptophan levels in the steatohepatitis-diet group. CONCLUSIONS: The findings of this study revealed an aspect of liver-muscle interaction, which might be important in developing treatments for sarcopenia associated with liver diseases.

Experiences of Disabled Older Adults in Urban Area Adult Day Care Centers: A Multisite Case Study.

This study described clients' experiences within adult day care (ADC) and its related impacts. A multisite case study was conducted with 26 older adults from six ADCs in Tokyo, with interviews and field observations conducted between November 2020 and July 2022. The transcribed interviews and field notes were analyzed qualitatively. Three categories pertaining to context ("guilt and resignation to the current living conditions," "desire for social connection despite frustrating limitations," and "supported life based on weekly ADC routine") and four categories about the experiences within ADC ("savoring disability- and age-friendly conversations," "feeling happy about something new and positive," "challenges for changes in self-image," and "discomfort with others and the waste of time") were extracted. Clients' increased vulnerability due to disabilities and COVID-19 affected their experiences. ADCs provide a safe place for interaction, and their use must be encouraged to develop a disability- and age-friendly society.

Experiences of Disabled Older Adults in Tokyo's Adult Day Care Centers during COVID-19-A Case Study.

The COVID-19 pandemic resulted in social isolation among elderly people with disabilities. Adult daycare (ADC) is an important community care option for socialization among people with disabilities. However, their experiences with ADC remain underexplored. Thus, this study investigated the experiences of community-dwelling disabled elderly with ADC from the perspective of socialization. Four older women from Tokyo with disabilities, availing of one ADC service, were interviewed across two sessions between November 2020 and January 2021. The transcribed interviews and field notes were analyzed qualitatively. This yielded eight categories: two pertaining to context ("restricted social interaction outside of ADC", "feeling simultaneously grateful and ashamed of oneself as a recipient of care services"), and six pertaining to experience with ADC ("take a catastrophic defensive posture in situations where one's perception of value is shaken", "express oneself positively to justify one's daily life", "have trouble knowing what to do", "put oneself in a shaded exchange relationship", "examine the value of elderly people in need of care in society", and "savor regular contact with others"). Ensuring the use of ADC as a safe place for interaction while considering pandemic-related needs is important to develop policy and practical responses to restricted socialization during COVID-19.

Intraluminal diamond-like carbon coating with anti-adhesion and anti-biofilm effects for uropathogens: A novel technology applicable to urinary catheters.

OBJECTIVES: To examine anti-adhesion and anti-biofilm effects of a diamond-like carbon coating deposited via a novel technique on the inner surface of a thin silicon tube. METHODS: Diamond-like carbon coatings were deposited into the lumen of a silicon tube with inner diameters of 2 mm. The surface of the diamond-like carbon was evaluated using physicochemical methods. We used three clinical isolates including green fluorescent protein-expressing Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus. We employed a continuous flow system for evaluation of both bacterial adhesion and biofilm formation. Bacterial adhesion assays consisted of counting the number of colony-forming units and visualization of adhered bacterial cells by scanning electron microscope to evaluate the diamond-like carbon-coated/uncoated samples. The biofilm structure was analyzed by confocal laser scanning microscopy on days 3, 5, 7 and 14 for green fluorescent protein-expressing Pseudomonas aeruginosa. RESULTS: The smooth and carbon-rich structure of the intraluminal diamond-like carbon film remained unchanged after the experiments. The numbers of colony-forming units suggested lower adherence of green fluorescent protein-expressing Pseudomonas aeruginosa and Escherichia coli in the diamond-like carbon-coated samples compared with the uncoated samples. The scanning electron microscope images showed adhered green fluorescent protein-expressing Pseudomonas aeruginosa cells without formation of microcolonies on the diamond-like carbon-coated samples. Finally, biofilm formation on the diamond-like carbon-coated samples was lower until at least day 14 compared with the uncoated samples. CONCLUSIONS: Intraluminal diamond-like carbon coating on a silicone tube has anti-adhesion and anti-biofilm effects. This technology can be applied to urinary catheters made from various materials.

Unexpectedly high thermostability of an NADP-dependent malic enzyme from a psychrophilic bacterium, Shewanella livingstonensis Ac10.

Psychrophilic enzymes are generally active at low temperatures, and their functions have attracted much interest in food processing, biochemical research, and chemical industry. However, their activities are usually lost above their growth temperature because of their flexible and unstable structure. Here, we unexpectedly found that a homodimeric NADP-dependent malic enzyme from a psychrophilic bacterium, Shewanella livingstonensis Ac10 (SL-ME) showed sufficient activity with 60°C treatment, similar to its counterpart from mesophilic Escherichia coli (MaeB). Consistently, SL-ME and MaeB irreversibly denatured at 71.9°C and 64.5°C, respectively. Therefore, SL-ME shows robust catalytic activity, which appears to be advantageous for its application in the bioconversion of NADP to NADPH, an essential ingredient for membrane phospholipid synthesis.

The Multi-Domain Intervention Trial in Older Adults With Diabetes Mellitus for Prevention of Dementia in Japan: Study Protocol for a Multi-Center, Randomized, 18-Month Controlled Trial.

Background: The Japan-Multi-domain Intervention Trial for Prevention of Dementia in Older Adults with Diabetes (J-MIND-Diabetes) is an 18-month, multi-centered, open-labeled, randomized controlled trial designed to identify whether multi-domain intervention targeting modifiable risk factors for dementia could prevent the progression of cognitive decline among older adults with type 2 diabetes mellitus (T2DM). This manuscript describes the study protocol for the J-MIND-Diabetes trial. Materials and Methods: Subjects of this trial will comprise a total of 300 T2DM outpatients aged 70-85 years with mild cognitive impairment. Subjects will be centrally randomized into intervention and control groups at a 1:1 allocation ratio using the stratified permuted-block randomization methods. The intervention group will participate in multi-domain intervention programs aimed at: (1) management of metabolic and vascular risk factors; (2) physical exercise and self-monitoring of physical activity; (3) nutritional guidance; and (4) social participation. The control group will receive usual T2DM care and general instructions on dementia prevention. The primary and secondary outcomes will be assessed at baseline, at 6- and 18-month follow-up. The primary outcome is change from baseline at 18 months in a global composite score combining several neuropsychological domains, including global cognitive function, memory, attention, executive function, processing speed and language. Secondary outcomes include: (1) cognitive changes in neuropsychological tests; (2) changes in geriatrics assessments; (3) metabolic control and diabetic complications; (4) changes in blood and urinary markers. Discussion: This trial will be the first trial to demonstrate the effectiveness of multi-domain intervention in preventing cognitive decline in older adults with T2DM at increased risk of dementia in Japan. Trial Registration: UMIN000035911; Registered on the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) 18 February 2019. (https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000040908).

Chemotactic disruption as a method to control bacterial wilt caused by Ralstonia pseudosolanacearum.

We have demonstrated that chemotaxis to l-malate facilitated motility of Ralstonia pseudosolanacearum MAFF 106611, a causative agent of bacterial wilt, to plant roots. Here, we evaluated the assumption that the disruption of chemotaxis to l-malate leads to inhibition of plant infection by R. pseudosolanacearum MAFF 106611. Chemotactic assays revealed that chemotaxis to l-malate was completely or partially inhibited in the presence of l-, d-, and dl-malate, respectively. Moreover, l-malate served as a carbon and energy source for R. pseudosolanacearum MAFF 106611, while d-malate inhibited the growth of this bacterium. In the sand-soak inoculation virulence assay for tomato plants, the addition of l-, d-, and dl-malate to sand suppressed the plant infection. We concluded that supplementation of l- and dl-malate suppresses tomato plant infection with R. pseudosolanacearum MAFF 106611 by disrupting its chemotaxis to l-malate, while d-malate suppresses it by both the disruption of l-malate chemotaxis and inhibition of growth.

Psychrophile-based simple biocatalysts for effective coproduction of 3-hydroxypropionic acid and 1,3-propanediol.

3-Hydroxypropionic acid (3-HP) and 1,3-propanediol (1,3-PDO) have tremendous potential markets in many industries. This study evaluated the simultaneous biosynthesis of the 2 compounds using the new psychrophile-based simple biocatalyst (PSCat) reaction system. The PSCat method is based on the expression of glycerol dehydratase, 1,3-propanediol dehydrogenase, and aldehyde dehydrogenase from Klebsiella pneumoniae in Shewanella livingstonensis Ac10 and Shewanella frigidimarina DSM 12253, individually. Heat treatment at 45 °C for 15 min deactivated the intracellular metabolic flux, and the production process was started after adding substrate, cofactor, and coenzyme. In the solo production process after 1 h, the maximum production of 3-HP was 62.0 m m. For 1,3-PDO, the maximum production was 25.0 m m. In the simultaneous production process, productivity was boosted, and the production of 3-HP and 1,3-PDO increased by 13.5 and 4.9 m m, respectively. Hence, the feasibility of the individual production and the simultaneous biosynthesis system were verified in the new PSCat approach.

Advanced appendiceal goblet cell carcinoids with intestinal obstruction: two case reports.

A goblet cell carcinoid is quite rare and has features, wherein, a carcinoid-like image and an adenocarcinoma-like image coexist. We encountered two cases of rare goblet cell carcinoid originating in the appendix. Case 1 is that of a 48-year-old man with a chief complaint of abdominal distension and case 2 is that of a 64-year-old woman with a chief complaint of constipation. At the time of diagnosis, both cases had already metastasized to the peritoneum and other organs, and no radical surgical treatment could be administered in either case. Chemotherapies were performed according to the regimen for colon cancer, and they were effective to a certain extent. During the course of treatment, however, both cases developed intestinal obstruction, presumably due to peritoneal dissemination, which led to worse condition and death several months afterwards. Chemotherapy for goblet cell carcinoids has not yet reached a consensus, and further studies and establishment of therapeutic strategy are desired in the future.

Efficient production of 1,3-propanediol by psychrophile-based simple biocatalysts in Shewanella livingstonensis Ac10 and Shewanella frigidimarina DSM 12253.

1,3-Propanediol (1,3-PDO) is a valuable compound with a large potential market in many industries. This study aimed to evaluate the abilities of the Psychrophile-based Simple bioCatalyst (PSCat) reaction system to biosynthesize 1,3-PDO. This biocatalyst has a potential platform that replaces the chemical-based production counterparts. The two genes involved in the metabolic pathway were expressed both individually and together in the psychrophilic host bacterium. The intracellular metabolic flux was deactivated using heat treatment, at 45 °C for 15 min. After individual gene expression (25.0 mM), 1,3-PDO productivity of the cells increased by approximately 2.5 times, in comparison to when genes were expressed together (10.2 mM). Productivity was boosted (31.1 mM) when the cofactor regeneration system was activated in the biocatalyst. Hence, both the ability of individual gene expression and the cofactor regeneration system were verified in the PSCat approach. Nonetheless, further research is necessary to develop and optimize this process for industrial production.

Characterization of methyl-accepting chemotaxis proteins (MCPs) for amino acids in plant-growth-promoting rhizobacterium Pseudomonas protegens CHA0 and enhancement of amino acid chemotaxis by MCP genes overexpression.

Pseudomonas protegens CHA0, known as plant-growth-promoting rhizobacterium, showed positive chemotactic responses toward proteinaceous L-amino acids. Genomic analysis revealed that P. protegens CHA0 possesses four putative chemoreceptors for amino acids (designated CtaA, CtaB, CtaC, and CtaD, respectively). Pseudomonas aeruginosa PCT2, a mutant defective in chemotaxis to amino acids, harboring a plasmid containing each of ctaA, ctaB, ctaC, and ctaD showed chemotactic responses to 20, 4, 4, and 11 types of amino acids, respectively. To enhance chemotaxis toward amino acids, we introduced the plasmids containing ctaA, ctaB, ctaC, or ctaD into P. protegens CHA0. By overexpression of the genes, we succeeded in enhancing chemotaxis toward more than half of the tested ligands. However, unexpectedly, the P. protegens CHA0 transformants showed unchanged or decreased responses to some amino acids when compared to wild-type CHA0. We speculate that alternation of expression of a chemoreceptor may affect the abundance of other chemoreceptors. ABBREVIATIONS: cDNA: complementary DNA; LBD: ligand-binding domain; MCP: methyl-accepting chemotaxis protein; PDC: PhoQ/DcuS/CitA; PGPR: plant-growth-promoting rhizobacteria; qRT-PCR: quantitative reverse transcription PCR.

Alpha-Glucosidase Inhibitor Voglibose Suppresses Azoxymethane-Induced Colonic Preneoplastic Lesions in Diabetic and Obese Mice.

Type 2 diabetes mellitus and its related insulin resistance are known to increase the risk of cancer. Anti-diabetic agents can improve insulin resistance and may lead to the suppression of carcinogenesis. This study aimed to investigate the preventive effects of the alpha-glucosidase inhibitor voglibose on the development of azoxymethane-induced colorectal pre-neoplastic lesions in obese and diabetic C57BL/KsJ-db/db mice. The direct effects of voglibose on the proliferation of colorectal cancer cells were also evaluated. Mice were injected with azoxymethane to induce colorectal pre-malignancy and were then administered drinking water with or without voglibose. At the end of the study, the administration of voglibose significantly suppressed the development of colorectal neoplastic lesions. In voglibose-treated mice, serum glucose levels, oxidative stress, as well as mRNA expression of the insulin-like growth factor-1 in the colon mucosa, were reduced. The proliferation of human colorectal cancer cells was not altered by voglibose. These results suggested that voglibose suppressed colorectal carcinogenesis in a diabetes- and obesity-related colorectal cancer model, presumably by improving inflammation via the reduction of oxidative stress and suppressing of the insulin-like growth factor/insulin-like growth factor-1 receptor axis in the colonic mucosa.

Accelerating itaconic acid production by increasing membrane permeability of whole-cell biocatalyst based on a psychrophilic bacterium Shewanella livingstonensis Ac10.

Whole-cell biocatalysts have numerous advantages including ease of preparation and coenzyme recovery over purified industrially used enzymes. However, the cell membrane can occasionally hinder cytoplasmic diffusion of the substrate, resulting in reduced biotransformation efficiency. Psychrophiles can grow and reproduce at low temperatures; their cell membranes are highly flexible, and their permeability can be improved via heat treatment at a moderate temperature. The aim of this study was to generate a psychrophile-based simple biocatalyst (PSCats) using Shewanella livingstonensis Ac10. This biocatalyst contained two enzymes that were heterologously expressed and converted citric acid to itaconic acid, thereby serving as a potential platform replacing the petroleum-based counterparts. The efficiency of the biocatalyst was increased via heat treatment at 45 °C for 15 min, and itaconic acid productivity of the cells after heat treatment (1.41 g/L/h) was increased around 6-fold in comparison with those without heat treatment (0.22 g/L/h). A large part of the productivity remained (67.3 %) when the cells were reused for 5 times (10 h for each reaction). Therefore, the potential of this heat-permeabilized psychrophile host to increase the productivity of whole-cell biocatalyst was proved; however, further research is necessary to understand the underlying mechanism.

Combined simultaneous enzymatic saccharification and comminution (SESC) and anaerobic digestion for sustainable biomethane generation from wood lignocellulose and the biochemical characterization of residual sludge solid.

Simultaneous enzymatic saccharification and comminution (SESC) was used for large-scale anaerobic digestion of wood lignocellulose to generate methane and unmodified lignin. During SESC, 10% aqueous mixture of powdered debarked wood from various species was subjected to bead milling with hydrolytic enzymes to generate particles below 1 µm. This slurry was directly used as a cosubstrate for anaerobic digestion in a 500 L stirred-tank reactor. Temperature and hydraulic retention time (HRT) were maintained at 50 °C and 30 days, respectively. At stable operation periods, an average yield of 224 L of methane per kg of cedar was attained. Comparable yields were achieved with red pine, elm, oak, and cedar bark. High-throughput microbial analysis established the presence of a relevant community to support the elevated level of methane production. The stability of the unmodified lignin in anaerobic digestion was also confirmed, allowing for its recovery as an important by-product.

Ethanol yield and sugar usability in thermophilic ethanol production from lignocellulose hydrolysate by genetically engineered Moorella thermoacetica.

Bioconversion from inexpensive renewable resource, such as biomass, to liquid fuel is one of the promising technologies to reduce the use of petroleum. We previously reported the genetically engineered Moorella thermoacetica could produce ethanol from the lignocellulosic feedstock. However, it was still unclear which carbon source in the substrate was preferentially consumed to produce ethanol. To identify the hierarchy of the sugar utilization during ethanol fermentation of this strain, we analyzed the sugar composition of lignocellulosic feedstock, and consumption rate of sugars during the fermentation process. The hydrolysates after acid pretreatment and enzymatic saccharification contained glucose, xylose, galactose, arabinose, and mannose. Time course data suggested that xylose was the most preferred carbon source among those sugars during ethanol fermentation. Ethanol yield was 0.40 ± 0.06 and 0.40 ± 0.12 g/g-total sugar, from lignocellulosic hydrolysates of Japanese cedar (Cryptomeria japonica) and rice straw (Oryza sativa), respectively. The results demonstrated that the genetically engineered M. thermoacetica is a promising candidate for thermophilic ethanol fermentation of lignocellulosic feedstocks, especially hemicellulosic sugars.

Suppressive effects of the sodium­glucose cotransporter 2 inhibitor tofogliflozin on colorectal tumorigenesis in diabetic and obese mice.

Sodium­glucose cotransporter 2 inhibitors were developed for the treatment of diabetes mellitus. Although recent studies have indicated that sodium­glucose cotransporter 2 inhibitors have suppressive effects on several types of cancer, their effects against colorectal cancer remain unknown. The purpose of the present study was to investigate the effects of tofogliflozin, a sodium­glucose cotransporter 2 inhibitor, on the development of colorectal cancer in diabetic and obese mice. The direct effects of tofogliflozin on the proliferation of colorectal cancer cells were also evaluated. C57BL/KsJ­db/db mice were injected with azoxymethane to induce colorectal pre­malignancy and they received drinking water with or without tofogliflozin. At the end of the study, administration of tofogliflozin was revealed to significantly suppress the development of colorectal neoplastic lesions and ß­catenin accumulated crypts. In the tofogliflozin­treated mice, the levels of blood glucose and serum TNF­α, as well as mRNA expression of the pro­inflammatory markers in the white adipose tissue, were reduced. Furthermore, macrophage infiltrations in the white adipose tissues were also reduced significantly. The proliferation of the sodium­glucose cotransporter 2­expressing human colorectal cancer cells was not altered by tofogliflozin. These results indicated that tofogliflozin ameliorated chronic inflammation and hyperglycemic condition leading to prevention of colorectal tumorigenesis in a diabetes­ and obesity­related colorectal cancer model.