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McKenzie BA, Chen FL, Gruen ME, Olby NJ. Canine Geriatric Syndrome: A Framework for Advancing Research in Veterinary Geroscience. Front Vet Sci 2022; 9:853743. [PMID: 35529834 PMCID: PMC9069128 DOI: 10.3389/fvets.2022.853743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 03/23/2022] [Indexed: 12/26/2022] Open
Abstract
Biological aging is the single most important risk factor for disease, disability, and ultimately death in geriatric dogs. The effects of aging in companion dogs also impose significant financial and psychological burdens on their human caregivers. The underlying physiologic processes of canine aging may be occult, or early signs of aging may be ignored because of the misconception that biological aging is natural and therefore inevitable. The ability to detect, quantify, and mitigate the deleterious processes of canine aging would greatly enhance veterinary preventative medicine and animal welfare. In this paper we propose a new conceptual framework for aging in dogs, the Canine Geriatric Syndrome (CGS). CGS consists of the multiple, interrelated physical, functional, behavioral, and metabolic changes that characterize canine aging as well as the resulting clinical manifestations, including frailty, diminished quality of life, and age-associated disease. We also identify potential key components of a CGS assessment tool, a clinical instrument that would enable veterinarians to diagnose CGS and would facilitate the development and testing of interventions to prolong healthspan and lifespan in dogs by directly targeting the biological mechanisms of aging. There are many gaps in our knowledge of the mechanisms and phenotype of aging in dogs that must be bridged before a CGS assessment tool can be deployed. The conceptual framework of CGS should facilitate identifying these gaps and should stimulate research to better characterize the processes and effects of aging in dogs and to identify the most promising preventative strategies to target these.
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Affiliation(s)
| | - Frances L. Chen
- Cellular Longevity Inc., dba Loyal, San Francisco, CA, United States
| | - Margaret E. Gruen
- College of Veterinary Medicine, North Carolina State University, Raleigh, NC, United States
| | - Natasha J. Olby
- College of Veterinary Medicine, North Carolina State University, Raleigh, NC, United States
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2
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Pöppl ÁG, Valle SC, Mottin TS, Leal JS, González FHD, Kucharski LC, Da Silva RSM. Pyometra-associated insulin resistance assessment by insulin binding assay and tyrosine kinase activity evaluation in canine muscle tissue. Domest Anim Endocrinol 2021; 76:106626. [PMID: 33866106 DOI: 10.1016/j.domaniend.2021.106626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/03/2021] [Accepted: 03/16/2021] [Indexed: 11/18/2022]
Abstract
Diestrus is associated with insulin resistance in bitches and pyometra can further impair insulin sensitivity. This study aimed to compare insulin sensitivity, insulin binding, and tyrosine kinase activity in bitches in anestrus, diestrus, or with pyometra. Patients submitted to elective ovariohysterectomy were divided into anestrus (n = 11) or diestrus (n = 13) according to reproductive history, vaginal cytology, and uterine histology. The group pyometra (n = 8) included bitches diagnosed with the disease based on clinical presentation and abdominal ultrasound findings and further confirmed by uterine histopathology. All patients were submitted to an intravenous glucose tolerance test (IVGTT) before ovariohysterectomy, and rectus abdominis muscle samples were collected during surgery for plasmatic membrane suspension preparation. Muscle-membranes were submitted to cold saturation insulin binding assay for dissociation constant (Kd) and maximum binding capacity (Bmax) determination, as well as exogenous substrate Poly (Glu: Tyr 4:1) phosphorylation assay for basal tyrosine kinase evaluation. Bitches with pyometra showed higher basal insulin (P < 0.001) and higher area under the curve (AUC) for insulin (P = 0.01) and glucose (P < 0.001) response during the IVGTT in comparison with bitches in anestrus or diestrus. Diestrus (P < 0.0001) and pyometra (P = 0.001) were associated with reduced tyrosine kinase activity in comparison with anestrus. No differences were documented in Kd and Bmax results for the low-affinity/high-capacity insulin receptors; however, high-affinity/low-capacity insulin receptors showed higher Kd and Bmax results in bitches in diestrus or with pyometra (P < 0.05) in comparison with anestrus. Despite the pyometra group showed the highest Kd values (P < 0.01), its Bmax results did not differ from the diestrus group (P > 0.05). Diestrus' higher Kd values and reduced tyrosine kinase activity in muscle tissue were compensated by increased total insulin binding capacity. Absent differences in IVGTT results between diestrus and anestrus bitches corroborate this finding. However, in bitches with pyometra, the highest Kd values were not compensated by increased total insulin binding capacity. This finding was associated with insulin resistance and glucose intolerance in IVGTT results. Moreover, pyometra resolution restored insulin sensitivity and glucose tolerance. These features can play a key role in pyometra-associated CDM, as well as in diabetic remission after pyometra resolution.
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Affiliation(s)
- Á G Pöppl
- Laboratório de Metabolismo e Endocrinologia Comparada, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Sarmento Leite 500, Porto Alegre - RS, Brazil. CEP: 90050-170; Departamento de Medicina Animal, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9090, Porto Alegre - RS, Brazil. CEP: 91540-000; Hospital de Clínicas Veterinárias, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9090, Porto Alegre - RS, Brazil. CEP: 91540-000.
| | - S C Valle
- Laboratório de Metabolismo e Endocrinologia Comparada, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Sarmento Leite 500, Porto Alegre - RS, Brazil. CEP: 90050-170
| | - T S Mottin
- Hospital de Clínicas Veterinárias, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9090, Porto Alegre - RS, Brazil. CEP: 91540-000
| | - J S Leal
- Setor de Patologia Veterinária, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9090, Porto Alegre - RS, Brazil. CEP: 91540-000
| | - F H D González
- Departamento de Patologia Clínica Veterinária, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Bento Gonçalves 9090, Porto Alegre - RS, Brazil. CEP: 91540-000
| | - L C Kucharski
- Laboratório de Metabolismo e Endocrinologia Comparada, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Sarmento Leite 500, Porto Alegre - RS, Brazil. CEP: 90050-170
| | - R S M Da Silva
- Laboratório de Metabolismo e Endocrinologia Comparada, Departamento de Fisiologia, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul (UFRGS), Av. Sarmento Leite 500, Porto Alegre - RS, Brazil. CEP: 90050-170
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Mizorogi T, Kobayashi M, Ohara K, Okada Y, Yamamoto I, Arai T, Kawasumi K. Effects of Age on Inflammatory Profiles and Nutrition/Energy Metabolism in Domestic Cats. VETERINARY MEDICINE (AUCKLAND, N.Z.) 2020; 11:131-137. [PMID: 33262938 PMCID: PMC7695597 DOI: 10.2147/vmrr.s277208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 10/27/2020] [Indexed: 11/23/2022]
Abstract
BACKGROUND Animals tend to increase in body weight and body condition score (BCS) with aging. Serum diagnostic markers related to energy metabolism may show changes even in healthy cats with aging. MATERIALS AND METHODS Seventy domestic cats were recruited for this study. Based upon the modified AAFP-AAHA Feline Life Stage Guidelines, animals were divided into six groups: Junior (7 months-2 years), Prime (3 -6 years), Mature (7-10 years), Senior (11-14 years), Geriatric-obese (15 years ≤) and Geriatric-thin (15 years ≤). Their body condition scores (BCS) ranged from 3/9 to 9/9. Changes in metabolites, inflammatory markers, hormone concentrations and enzyme activities related to energy metabolism were investigated in serum of 70 domestic cats of various ages. RESULTS Serum glucose (GLU) concentrations in the Mature, Senior, and Geriatric-obese groups were significantly higher than those in the Junior group. Serum amyloid A (SAA) concentrations in the Geriatric-thin group were significantly increased compared with the Junior group. SAA concentrations in the Geriatric-obese group tended to increase although there were no statistically significant differences. In the Mature, Senior, Geriatric-obese and Geriatric-thin groups, malate dehydrogenase/lactate dehydrogenase (M/L) ratio, an energy metabolic indicator, tended to decrease compared with the Junior group. In the Senior group, triglyceride (TG) concentrations were significantly increased compared with the Junior group. In the Geriatric-obese and Geriatric-thin groups, blood urea nitrogen (BUN) concentrations were significantly increased compared with the Junior group. In the Geriatric-obese group, albumin (ALB) concentrations were decreased compared with the Junior group. CONCLUSION Aged domestic cats tend to increase in body weight and BCS. In addition, serum GLU, TG, SAA, and BUN concentrations increased and serum ALB concentrations and M/L ratio decreased. These diagnostic markers may be useful to detect small changes related to energy metabolism with aging that may cause obesity with light inflammation in healthy cats.
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Affiliation(s)
- Takayuki Mizorogi
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan
- Seijyo Kobayashi Veterinary Clinic, Tokyo, Japan
| | | | - Kenji Ohara
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry & Fisheries, Government of Japan, Tokyo, Japan
| | - Yuki Okada
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan
| | - Ichiro Yamamoto
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan
| | - Toshiro Arai
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan
| | - Koh Kawasumi
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo, Japan
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Kobayashi M, Okada Y, Ueno H, Mizorogi T, Ohara K, Kawasumi K, Suruga K, Kadokura K, Ohnishi Y, Arai T. Effects of Supplementation with Anti-Inflammatory Compound Extracted from Herbs in Healthy and Obese Cats. VETERINARY MEDICINE-RESEARCH AND REPORTS 2020; 11:39-44. [PMID: 32215260 PMCID: PMC7084122 DOI: 10.2147/vmrr.s240516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 01/29/2020] [Indexed: 11/24/2022]
Abstract
Background Obesity has become a serious public health problem all over the world, and prevalence of obesity has increased in cats. Obesity is characterized by continuous low-grade inflammation based on oxidative stress by excessively produced reactive oxygen species (ROS). Supplementation with anti-oxidant and anti-inflammatory compounds is very effective to relieve the obesity condition. A plant extract mixture containing Rhus verniciflua and some other herbs, Rv-PEM01-99, shows anti-oxidant and anti-inflammatory effects in animals. The aim of this study was to evaluate the effects of supplementation with Rv-PEM01-99 as an anti-inflammatory compound in healthy and obese cats. Materials and Methods Ten healthy mix breed cats and four obesity disease cats were used. The healthy cats were randomly divided into control and test groups. Anti-inflammatory compound, Rv-PEM01-99, in which quercetin derivative is the main component, was supplemented to the healthy test group and the obesity disease cats at the dose of 100–120 mg/kg/day (2.5–3.0 mg/kg/day as quercetin) for 4 weeks. Metabolites, hormones and enzymes were measured before and after the compound supplementation. Results The anti-inflammatory compound supplementation decreased serum amyloid A (SAA) concentrations as inflammatory markers in both healthy and obesity disease cats. In obesity disease cats, plasma total cholesterol concentrations and AST and ALT activities decreased significantly after the compound supplementation. Conclusion Quercetin derivative seems to have strong anti-inflammatory activities. In the healthy cats, anti-inflammatory compound supplementation decreased plasma NEFA and SAA concentrations. In the obesity disease cats, the compound supplementation may have alleviated obesity disease by relieving inflammation and improvement of lipid metabolism in livers.
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Affiliation(s)
- Motoo Kobayashi
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo 180-8601, Japan.,One Health Co. Ltd, Tokyo 157-0066, Japan
| | - Yuki Okada
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo 180-8601, Japan.,One Health Co. Ltd, Tokyo 157-0066, Japan
| | - Hiromichi Ueno
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo 180-8601, Japan
| | - Takayuki Mizorogi
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo 180-8601, Japan
| | - Kenji Ohara
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo 180-8601, Japan
| | - Koh Kawasumi
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo 180-8601, Japan
| | - Kohei Suruga
- Food Function R&D Division, International Operation Department, Kibun Foods Inc., Tokyo 206-0812, Japan
| | - Kazunari Kadokura
- Food Function R&D Division, International Operation Department, Kibun Foods Inc., Tokyo 206-0812, Japan
| | | | - Toshiro Arai
- Laboratory of Veterinary Biochemistry, School of Veterinary Medicine, Nippon Veterinary and Life Science University, Tokyo 180-8601, Japan.,One Health Co. Ltd, Tokyo 157-0066, Japan
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Okada Y, Ueno H, Mizorogi T, Ohara K, Kawasumi K, Arai T. Diagnostic Criteria for Obesity Disease in Cats. Front Vet Sci 2019; 6:284. [PMID: 31508438 PMCID: PMC6718553 DOI: 10.3389/fvets.2019.00284] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/09/2019] [Indexed: 01/27/2023] Open
Abstract
Accumulated visceral and subcutaneous fat masses were measured with computed tomography (CT) in cats with various body condition scores (BCS) from 5/9 to 9/9. BCS does not always reflect visceral fat accumulation which induces pro-inflammatory reactions. Obese cats with accumulated visceral fat showed low plasma adiponectin and high serum amyloid A (SAA) concentrations, an inflammatory marker. Based on the above results, new diagnostic criteria for obesity disease were established as follows. For overweight cats with high BCS of >7/9, showing two or more of the following three symptoms, low adiponectin concentrations, hyperlipidemia, and high SAA concentrations, categorizes them as having obesity disease. Cats with BCS 6/9-9/9, without inflammatory reactions, were classified as simple obesity, which is similar to metabolically healthy obesity (MHO) defined in human medicine. Simple obesity group showed significantly higher adiponectin concentrations than those in control group. The obesity disease group showed significantly higher plasma triglyceride (TG) and SAA concentrations and lower concentrations of adiponectin than the control group. Moreover, plasma glucose and malondialdehyde (MDA) concentrations in the obesity disease group were higher than those in healthy control group, although the differences were not statistically significant. Establishing criteria for obesity disease based on visceral fat accumulation and inflammation markers levels contributes to early and correct diagnosis of obesity in cats.
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Affiliation(s)
- Yuki Okada
- School of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino, Japan
| | | | - Takayuki Mizorogi
- School of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino, Japan
| | - Kenji Ohara
- School of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino, Japan
| | - Koh Kawasumi
- School of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino, Japan
| | - Toshiro Arai
- School of Veterinary Medicine, Nippon Veterinary and Life Science University, Musashino, Japan
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Sato A, Sarentonglaga B, Ogata K, Yamaguchi M, Hara A, Atchalalt K, Sugane N, Fukumori R, Nagao Y. Effects of insulin-like growth factor-1 on the in vitro maturation of canine oocytes. J Reprod Dev 2017; 64:83-88. [PMID: 29212962 PMCID: PMC5830362 DOI: 10.1262/jrd.2017-145] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The maturation rate of canine oocytes during in vitro maturation (IVM) needs to be improved. The present study was designed to evaluate the effects of insulin-like growth factor-1 (IGF-1) on the IVM of canine oocytes. Ovaries were obtained by ovariohysterectomy and were sliced to release cumulus-oocyte complexes (COCs). In Experiment 1, the effects of different concentrations of IGF-1 on the nuclear maturation of oocytes was investigated. The COCs were cultured in a modified medium (mTCM199) with IGF-1 (0, 0.5, 5, 10, and 50 µg/ml). At the end of the 48 h culture, oocytes were fixed and stained to evaluate their nuclear stage. Supplementation with 50 µg/ml IGF-1 induced a significantly higher metaphase II (MII) rate (P < 0.05) compared to the 0 and 0.5 μg/ml IGF-1 groups. In Experiment 2, the expression levels of insulin receptor (INSR), IGF-1 receptor (IGF-1R), and IGF-2 receptor (IGF-2R) genes, localized to canine oocytes and cumulus cells, were investigated before and after IVM. The expression level of IGF-1R in cumulus cells after IVM was higher than that before IVM (P < 0.05). In Experiment 3, it was investigated whether an inhibitor of PTEN (phosphatase and tensin homolog), bpV, affects the nuclear maturation of oocytes. Regardless of bpV supplementation at a concentration of 0.2 to 200 µmol/l, there was no significant difference in the proportion of oocytes that reached the MII stage. These results indicated that IGF-1 has a favorable effect on the IVM of canine oocytes, possibly through the stimulation of the Ras/MAPK pathway via IGF-1R expressed in cumulus cells.
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Affiliation(s)
- Akane Sato
- University Farm, Faculty of Agriculture, Utsunomiya University, Tochigi 321-4415, Japan.,Department of Animal Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-0054, Japan
| | | | - Kazuko Ogata
- University Farm, Faculty of Agriculture, Utsunomiya University, Tochigi 321-4415, Japan.,Present: National Livestock Breeding Center, Fukushima 961-8061, Japan
| | - Mio Yamaguchi
- University Farm, Faculty of Agriculture, Utsunomiya University, Tochigi 321-4415, Japan.,Present: Local Independent Administrative Agency Hokkaido Research Organization, Hokkaido 081-0038, Japan
| | - Asuka Hara
- University Farm, Faculty of Agriculture, Utsunomiya University, Tochigi 321-4415, Japan.,Department of Animal Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-0054, Japan
| | - Khurchabiling Atchalalt
- University Farm, Faculty of Agriculture, Utsunomiya University, Tochigi 321-4415, Japan.,Department of Animal Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-0054, Japan
| | - Naoko Sugane
- East Japan Guide Dog Association, Tochigi 321-0342, Japan
| | - Rika Fukumori
- University Farm, Faculty of Agriculture, Utsunomiya University, Tochigi 321-4415, Japan.,Present: Rakuno Gakuen University, Hokkaido 069-0836, Japan
| | - Yoshikazu Nagao
- University Farm, Faculty of Agriculture, Utsunomiya University, Tochigi 321-4415, Japan.,Department of Animal Production Science, United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Tokyo 183-0054, Japan
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Zhuo MQ, Pan YX, Wu K, Xu YH, Zhang LH, Luo Z. IRS1 and IRS2: molecular characterization, tissue expression and transcriptional regulation by insulin in yellow catfish Pelteobagrus fulvidraco. FISH PHYSIOLOGY AND BIOCHEMISTRY 2017; 43:619-630. [PMID: 27864748 DOI: 10.1007/s10695-016-0316-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 11/08/2016] [Indexed: 06/06/2023]
Abstract
The insulin receptor substrate (IRS) proteins, in particular, IRS1 and IRS2, are the key downstream players of insulin signaling pathway and the regulation of lipid metabolism. In the present study, two genes of IRS (IRS1 and IRS2) were isolated and characterized from yellow catfish Pelteobagrus fulvidraco. Their molecular characterizations, tissue expressions, and transcriptional levels by insulin both in vivo and in vitro were determined. The validated complementary DNAs encoding for IRS1 and IRS2 were 3693 and 3177 bp in length, encoding proteins of 1230 and 1058 amino acid residues, respectively. Similarly to mammals, amino acid sequence alignment revealed that IRSs contained an N-terminal pleckstrin homology (PH) domain, a phosphotyrosine-binding (PTB) domain, and several C-terminal multiple sites of tyrosine phosphorylation. Both IRS1 and IRS2 were widely expressed across the ten tissues (liver, white muscle, spleen, brain, gill, mesenteric fat, anterior intestine, heart, mid-kidney, and ovary), but at the variable levels. Insulin injection at 1 μg/g in vivo significantly stimulated the messenger RNA (mRNA) expression of IRS2, but not IRS1 mRNA expression levels in the liver of yellow catfish after 48 h. In hepatocytes of yellow catfish, insulin incubation significantly stimulated the IRS1 (at a 1000 nM insulin group) and IRS2 (at both 100 and 1000 nM insulin groups) mRNA expressions, which indicated that IRS2 was more sensitive than IRS1 to insulin stimulation in the liver of yellow catfish, and IRS2 played a more important role in mediating insulin's effects on the liver metabolism. The present study serves to increase our understanding into the function of IRS in fish.
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Affiliation(s)
- Mei-Qin Zhuo
- Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture of P. R. C., Fishery College, Huazhong Agricultural University, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan, 430070, China
| | - Ya-Xiong Pan
- Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture of P. R. C., Fishery College, Huazhong Agricultural University, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan, 430070, China
| | - Kun Wu
- Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture of P. R. C., Fishery College, Huazhong Agricultural University, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan, 430070, China
| | - Yi-Huan Xu
- Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture of P. R. C., Fishery College, Huazhong Agricultural University, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan, 430070, China
| | - Li-Han Zhang
- Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture of P. R. C., Fishery College, Huazhong Agricultural University, Wuhan, 430070, China
- Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan, 430070, China
| | - Zhi Luo
- Key Laboratory of Freshwater Animal Breeding Ministry of Agriculture of P. R. C., Fishery College, Huazhong Agricultural University, Wuhan, 430070, China.
- Freshwater Aquaculture Collaborative Innovative Centre of Hubei Province, Wuhan, 430070, China.
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Okada Y, Kobayashi M, Sawamura M, Arai T. Comparison of Visceral Fat Accumulation and Metabolome Markers among Cats of Varying BCS and Novel Classification of Feline Obesity and Metabolic Syndrome. Front Vet Sci 2017; 4:17. [PMID: 28261588 PMCID: PMC5306360 DOI: 10.3389/fvets.2017.00017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 01/30/2017] [Indexed: 01/23/2023] Open
Abstract
As in humans, obesity and its associated diseases represent the most significant threat to the health of veterinary populations. Previous human studies have provided insights into the risk factors of obesity, complex pathogenesis of obesity-associated diseases, and their life-threatening consequences. In humans, the “metabolic syndrome” represents a cluster of metabolic risk factors associated with the development of cardiovascular disease. Risk factors for metabolic syndrome, such as diabetes, obesity, high blood pressure, and its complications increase health-care utilization and medical expenses. Early diagnosis and intervention through preemptive approach is in need, and the new International Diabetes Federation definition of MS serves as the universally accepted diagnostic tool that is accessible in clinical settings. In veterinary populations, especially in cats, similar pathophysiological path and disease progression to the development of MS, such as adipokine dysregulations, chronic inflammation, lipotoxicity, are expected. The aim of this manuscript is twofold. First of all, it presents our preliminary feline obesity study that serves as the basis for discussion of obesity and its metabolic impact on feline population. In this study, we observed the effects of weight gain on energy metabolism using metabolome markers, such as adiponectin (ADN) and proinflammatory cytokines, in correlation with other common biochemical parameters in 14 clinically healthy cats of varying weight status. Further, we evaluated the visceral fat accumulation in three subjects of varying Body Condition Scores via computed tomography imaging and laparoscopic examination, and assessed the adipocyte type and size histologically. Mutually antagonizing changes in ADN and visceral adipose tissue (VAT) reflected the pathophysiological derangements leading to MS earlier than the common biochemical predictors such as glucose, liver values, and lipid markers. Second, it proposes the novel diagnostic and classification method of feline obesity and MS, based on the established diagnostic criteria of human MS and the presented study results. The results supported our novel “classification of feline obesity” and “Feline MS diagnostic criteria,” suggesting the need to complement ADN measurement with VAT volume to better understand the pathogenesis of metabolic disturbances in the feline population.
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Affiliation(s)
- Yuki Okada
- Department of Veterinary Bioscience, School of Veterinary Medicine, Nippon Veterinary and Life Science University , Musashino , Japan
| | | | | | - Toshiro Arai
- Department of Veterinary Bioscience, School of Veterinary Medicine, Nippon Veterinary and Life Science University , Musashino , Japan
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Osto M, Lutz TA. Translational value of animal models of obesity-Focus on dogs and cats. Eur J Pharmacol 2015; 759:240-52. [PMID: 25814247 DOI: 10.1016/j.ejphar.2015.03.036] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 01/15/2015] [Accepted: 03/12/2015] [Indexed: 12/11/2022]
Abstract
A prolonged imbalance between a relative increase in energy intake over a decrease in energy expenditure results in the development of obesity; extended periods of a positive energy balance eventually lead to the accumulation of abnormally high amounts of fat in adipose tissue but also in other organs. Obesity is considered a clinical state of impaired general heath in which the excessive increase in adipose tissue mass may be associated with metabolic disorders such as type 2 diabetes mellitus, hyperlipidemia, hypertension and cardiovascular diseases. This review discusses briefly the use of animal models for the study of obesity and its comorbidities. Generally, most studies are performed with rodents, such as diet induced obesity and genetic models. Here, we focus specifically on two different species, namely dogs and cats. Obese dogs and cats show many features of human obesity. Interestingly, however, dogs and cats differ from each other in certain aspects because even though obese dogs may become insulin resistant, this does not result in the development of diabetes mellitus. In fact, diabetes in dogs is typically not associated with obesity because dogs present a type 1 diabetes-like syndrome. On the other hand, obese cats often develop diabetes mellitus which shares many features with human type 2 diabetes; feline and human diabetes are similar in respect to their pathophysiology, underlying risk factors and treatment strategies. Our review discusses genetic and endocrine factors in obesity, discusses obesity induced changes in lipid metabolism and includes some recent findings on the role of gut microbiota in obesity. Compared to research in rodent models, the array of available techniques and tools is unfortunately still rather limited in dogs and cats. Hence, even though physiological and pathophysiological phenomena are well described in dogs and cats, the underlying mechanisms are often not known and studies investigating causality specifically are scarce.
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Affiliation(s)
- Melania Osto
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH 8057 Zurich, Switzerland
| | - Thomas A Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, CH 8057 Zurich, Switzerland; Institute of Laboratory Animal Science, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, Winterthurerstrasse 190, CH 8057 Zurich, Switzerland.
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Nozawa S, Oda H, Akiyama R, Ueda K, Saeki K, Shono S, Maruyama N, Murata A, Tazaki H, Mori A, Momota Y, Azakami D, Sako T, Ishioka K. Decreased gene expressions of insulin signal molecules in canine hyperadrenocorticism. J Vet Med Sci 2014; 76:1177-82. [PMID: 24829079 PMCID: PMC4155204 DOI: 10.1292/jvms.14-0033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Hyperadrenocorticism (HAC) is a common endocrine disorder in dogs, in which excess glucocorticoid causes insulin resistance. Disturbance of insulin action may be caused by multiple factors, including transcriptional modulation of insulin signal molecules which lie downstream of insulin binding to insulin receptors. In this study, gene expressions of insulin signal molecules were examined using neutrophils of the HAC dogs (the untreated dogs and the dogs which had been treated with trilostane). Insulin receptor substrate (IRS)-1, IRS-2, phosphatidylinositol 3-kinase (PI3-K), protein kinase B/Akt kinase (Akt)-2 and protein kinase C (PKC)-lambda were analyzed in the HAC dogs and compared with those from normal dogs. The IRS-1 gene expressions decreased by 37% and 35% of the control dogs in the untreated and treated groups, respectively. The IRS-2 gene expressions decreased by 61% and 72%, the PI3-K gene expressions decreased by 47% and 55%, and the Akt-2 gene expressions decreased by 45% and 56% of the control dogs, similarly. Collectively, gene expressions of insulin signal molecules are suppressed in the HAC dogs, which may partially contribute to the induction of insulin resistance.
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Affiliation(s)
- Satoshi Nozawa
- Laboratory of Biomolecular Chemistry, School of Veterinary Medicine, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan
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11
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Bermingham EN, Kittelmann S, Young W, Kerr KR, Swanson KS, Roy NC, Thomas DG. Post-weaning diet affects faecal microbial composition but not selected adipose gene expression in the cat (Felis catus). PLoS One 2013; 8:e80992. [PMID: 24312255 PMCID: PMC3842929 DOI: 10.1371/journal.pone.0080992] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2012] [Accepted: 10/17/2013] [Indexed: 12/11/2022] Open
Abstract
The effects of pre- (i.e., gestation and during lactation) and post-weaning diet on the composition of faecal bacterial communities and adipose expression of key genes in the glucose and insulin pathways were investigated in the cat. Queens were maintained on a moderate protein:fat:carbohydrate kibbled (“Diet A”; 35:20:28% DM; n = 4) or high protein:fat:carbohydrate canned (“Diet B”; 45:37:2% DM; n = 3) diet throughout pregnancy and lactation. Offspring were weaned onto these diets in a nested design (n = 5 per treatment). Faecal samples were collected at wk 8 and 17 of age. DNA was isolated from faeces and bacterial 16S rRNA gene amplicons were analysed by pyrosequencing. RNA was extracted from blood (wk 18) and adipose tissue and ovarian/testicular tissues (wk 24) and gene expression levels determined using RT-qPCR. Differences (P<0.05) in composition of faecal bacteria were observed between pregnant queens fed Diet A or B. However, pre-weaning diet had little effect on faecal bacterial composition in weaned kittens. In contrast, post-weaning diet altered bacterial population profiles in the kittens. Increased (P<0.05) abundance of Firmicutes (77% vs 52% of total reads) and Actinobacteria (0.8% vs 0.2% of total reads), and decreased (P<0.05) abundance of Fusobacteria (1.6% vs 18.4% of total reads) were observed for kittens fed the Diet A compared to those fed Diet B post-weaning. Feeding Diet B pre-weaning increased (P<0.05) the expression levels of INRS, LEPT, PAI-1 and tended to increase GLUT1, while the expression levels of IRS-1 in blood increased in kittens fed Diet A pre-weaning. Post-weaning diet had no effect on expression levels of target genes. Correlations between the expression levels of genes involved in glucose and insulin pathways and faecal Bacteriodetes and Firmicutes phyla were identified. The reasons for why post-weaning diet affects microbial populations and not gene expression levels are of interest.
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Affiliation(s)
- Emma N. Bermingham
- Food Nutrition & Health, AgResearch Grasslands, Palmerston North, New Zealand
- * E-mail:
| | - Sandra Kittelmann
- Animal Nutrition & Health, AgResearch Grasslands, Palmerston North, New Zealand
| | - Wayne Young
- Food Nutrition & Health, AgResearch Grasslands, Palmerston North, New Zealand
| | - Katherine R. Kerr
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Kelly S. Swanson
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Nicole C. Roy
- Food Nutrition & Health, AgResearch Grasslands, Palmerston North, New Zealand
- The Riddet Institute, Massey University, Palmerston North, New Zealand
| | - David G. Thomas
- Centre of Feline Nutrition, Institute of Food, Nutrition and Human Health, Massey University, Palmerston North, New Zealand
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12
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Gooding MA, Flickinger EA, Atkinson JL, Duncan IJH, Shoveller AK. Effects of high-fat and high-carbohydrate diets on fat and carbohydrate oxidation and plasma metabolites in healthy cats. J Anim Physiol Anim Nutr (Berl) 2013; 98:596-607. [PMID: 24033683 DOI: 10.1111/jpn.12126] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2011] [Accepted: 07/31/2013] [Indexed: 02/06/2023]
Abstract
High-fat (HF) or high-carbohydrate (HC) diets (30% fat, 18.9% carbohydrate; HF and 10% fat, 46.3% carbohydrate; HC) and lengths of adaptation were investigated in cats (Felis catus; 10 ± 2 months, 3.6 ± 0.3 kg). Cats randomly received each treatment for 14 days in a crossover design with a 14-day washout period between each diet. Three 22-h indirect calorimetry studies were conducted after acute (day 0), semichronic (day 4) and chronic (day 13) dietary exposure. Blood samples were collected after a 24-h fast on days 1, 5 and 14. When cats consumed the HC and HF diet, oxidation of the restricted nutrient exceeded intake while oxidation of the nutrient in excess matched intake. Mean max energy expenditure (EE) of cats consuming the HF and HC diet were 107 and 102 kcal/kg(0.67)/day and occurred at a mean of 4 and 12 h post-feeding respectively. Maximal fat (0.90 g/h) and carbohydrate (carbohydrate; 1.42 g/h) oxidation were attained at 26 min and 10.4 h post-feeding respectively. The changes observed in macronutrient oxidation and EE suggest that cats adapt whole-body nutrient metabolism in response to changes in dietary macronutrient content, but may require longer than 14 day to adapt to a macronutrient that is present at a lower concentration in the diet.
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Affiliation(s)
- M A Gooding
- University of Guelph, Animal and Poultry Science, Guelph, ON, Canada
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13
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de Godoy MRC, Swanson KS. COMPANION ANIMALS SYMPOSIUM: Nutrigenomics: Using gene expression and molecular biology data to understand pet obesity1. J Anim Sci 2013; 91:2949-64. [DOI: 10.2527/jas.2012-5860] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- M. R. C. de Godoy
- Department of Animal Sciences, University of Illinois, Urbana, IL 61801
| | - K. S. Swanson
- Department of Animal Sciences, University of Illinois, Urbana, IL 61801
- Division of Nutritional Sciences, University of Illinois, Urbana, IL 61801
- Department of Veterinary Clinical Medicine, University of Illinois, Urbana, IL 61801
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14
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IRS1 Expression in Hepatic Tissue and Leukocytes in Chronic Hepatitis C Virus Infected Patients: A Comparative Study. Int J Hepatol 2012; 2012:698905. [PMID: 22830036 PMCID: PMC3398587 DOI: 10.1155/2012/698905] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 04/18/2012] [Accepted: 05/04/2012] [Indexed: 02/07/2023] Open
Abstract
Aims. To determine lymphocyte IRS (IRS1 cells) in HCV patients, correlating it to liver IRS (IRS 1liver) and HOMA-IR. This study tested the hypothesis that IRS1 cells expression can be used as insulin resistance (IR) marker in HCV-infected patients. IRS1 cells were not studied before in HCV infection. Materials and Methods. HCV chronically infected patients, naïve, nonobese, noncirrhotic, and nondiabetic were prospectively included and compared to controls (blood donors). Blood was taken, and leukocytes were separated. IRS1 was determined by real-time PCR. Liver tissue was obtained from transplant donors as controls. Results. 41 HCV-positive patients were included, 26 males (60.5%); mean age of 45 (±7.9); 33 (80.5%) from genotype 1. 6 out of 12 controls were males (50%); mean age was 26.7 (±3.2). There was expression of IRS1 in leukocytes. The median IRS1 cells (HCV) were 0.061 (0.004 to 0.469); the median IRS 1liver (HCV) was 0.0003 (0.00002 to 0.0186)-lower than in controls (resp., P = 0.005 and P = 0.018). HOMA-IR had an inverse correlation with IRS 1liver (P = 0.04). There was no correlation between IRS1 liver and IRS1 cells (P = 0.930). Conclusions. There was expression of IRS1 in leukocytes. IRS1 cells and IRS1 liver were lower in HCV patients than in controls.
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Winnick JJ, An Z, Ramnanan CJ, Smith M, Irimia JM, Neal DW, Moore MC, Roach PJ, Cherrington AD. Hepatic glycogen supercompensation activates AMP-activated protein kinase, impairs insulin signaling, and reduces glycogen deposition in the liver. Diabetes 2011; 60:398-407. [PMID: 21270252 PMCID: PMC3028338 DOI: 10.2337/db10-0592] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE The objective of this study was to determine how increasing the hepatic glycogen content would affect the liver's ability to take up and metabolize glucose. RESEARCH DESIGN AND METHODS During the first 4 h of the study, liver glycogen deposition was stimulated by intraportal fructose infusion in the presence of hyperglycemic-normoinsulinemia. This was followed by a 2-h hyperglycemic-normoinsulinemic control period, during which the fructose infusion was stopped, and a 2-h experimental period in which net hepatic glucose uptake (NHGU) and disposition (glycogen, lactate, and CO(2)) were measured in the absence of fructose but in the presence of a hyperglycemic-hyperinsulinemic challenge including portal vein glucose infusion. RESULTS Fructose infusion increased net hepatic glycogen synthesis (0.7 ± 0.5 vs. 6.4 ± 0.4 mg/kg/min; P < 0.001), causing a large difference in hepatic glycogen content (62 ± 9 vs. 100 ± 3 mg/g; P < 0.001). Hepatic glycogen supercompensation (fructose infusion group) did not alter NHGU, but it reduced the percent of NHGU directed to glycogen (79 ± 4 vs. 55 ± 6; P < 0.01) and increased the percent directed to lactate (12 ± 3 vs. 29 ± 5; P = 0.01) and oxidation (9 ± 3 vs. 16 ± 3; P = NS). This change was associated with increased AMP-activated protein kinase phosphorylation, diminished insulin signaling, and a shift in glycogenic enzyme activity toward a state discouraging glycogen accumulation. CONCLUSIONS These data indicate that increases in hepatic glycogen can generate a state of hepatic insulin resistance, which is characterized by impaired glycogen synthesis despite preserved NHGU.
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Affiliation(s)
- Jason J Winnick
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
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16
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Mori A, Lee P, Sako T, Mizutani H, Arai T. Successful intensive insulin treatment of type 1 diabetic dogs leads to restoration of peripheral leukocyte insulin signaling gene expression and enzyme activities. J Vet Med Sci 2010; 71:1017-26. [PMID: 19721352 DOI: 10.1292/jvms.71.1017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to investigate whether intensive insulin treatment of dogs suffering from type 1 diabetes mellitus, resulting in tight glycemic control, could be reflected by changes in peripheral leukocyte metabolism. Specifically, plasma metabolites and enzyme activities were assessed. In addition, quantitative RT-PCR was used to determine changes in insulin signaling gene (insulin receptor substrate (IRS)-1, IRS-2 and phosphatidylinositol 3-kinase (PI3-K) P85alpha) mRNA levels in peripheral leukocytes. Lastly, leukocyte enzymes involved in cellular energy metabolism were examined for changes in glucose utilization. Our results indicated that intensive insulin treatment was successful in type 1 DM dogs, leading to tight glycemic control. The mean glucose concentration and glycated albumin percentage significantly decreased to 156 mg/dl and 15.6%, respectively, following treatment. In peripheral leukocytes, the IRS-2 and PI3-K p85alpha mRNA levels significantly increased, and a significant increase in pyruvate kinase and pyruvate carboxylase activity, two enzymes involved in cellular energy metabolism, was also observed post treatment. Therefore, the observed changes in insulin signaling pathway activity and cellular energy metabolism enzyme activity in peripheral leukocytes are considered to be characteristics of amelioration of glucose metabolism by insulin action. As such, peripheral leukocytes are sufficiently sensitive to monitor for improving glycemic control during intensive insulin treatment of type 1 DM dogs. Blood cells such as leukocytes are much more readily available than muscle or adipose tissue for studies in dogs.
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Affiliation(s)
- Akihiro Mori
- School of Veterinary Nursing & Technology, Nippon Veterinary and Life Science University, Tokyo, Japan.
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Mori A, Lee P, Takemitsu H, Iwasaki E, Kimura N, Yagishita M, Hayasaka M, Arai T. Decreased gene expression of insulin signaling genes in insulin sensitive tissues of obese cats. Vet Res Commun 2008; 33:315-29. [PMID: 18946721 DOI: 10.1007/s11259-008-9179-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Accepted: 09/22/2008] [Indexed: 12/31/2022]
Abstract
Type 2 diabetes mellitus (DM) animal models have provided ample opportunity for investigating pathogenesis, as well as to evaluate novel treatment and prevention options for the disease. Because the domestic cat shares a similar environment with humans, it is also confronted with many similar risk factors for diabetes, such as physical inactivity and obesity. Obesity is a significant risk factor for diabetes in cats, and as such, the domestic cat may serve as an ideal model for investigating obesity induced insulin resistance. This study determined changes in insulin signaling genes within insulin sensitive tissues of obese felines. Quantitative RT-PCR was performed to determine mRNA levels of three important insulin signaling genes which have been implicated with insulin resistance: insulin receptor substrate (IRS)-1, IRS-2, and phosphatidylinositol 3'-kinase (PI3-K) p85alpha. Obese cats had significantly lower IRS-2 and PI3-K p85alpha mRNA levels in liver and skeletal muscle as compared to control cats. This down regulation of insulin signaling genes in obese cats mirrors that of obese humans and rodents suffering from insulin resistance. Interestingly, preprandial blood tests indicated that our obese cats were no different from control cats with regards to glucose tolerance and insulin resistance, thus indicating that the obese cats used in our study had a moderate level of obesity. Therefore, insulin signaling gene alterations were occurring in insulin sensitive tissues of moderately obese felines before glucose intolerance was clinically evident. As such, the monitoring of key insulin signaling genes may have some important diagnostic value to determine the risk level and degree of obesity induced insulin resistance.
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Affiliation(s)
- A Mori
- Department of Veterinary Science, School of Veterinary Medicine, Nippon Veterinary and Life Science University, 1, 7, 1 Kyonancho, Musashino, Tokyo, Japan.
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