mRNA expression levels of cytochrome P450 CYP1A2, CYP3A4, and CYP3A5 in the epidermis: a focus on individual differences among Japanese individuals.

Various cytochrome P450 enzymes (CYPs) that contribute to drug metabolism are expressed in the skin. However, variation among individuals in CYP expression profiles is not well-understood.To investigate CYPs related to the metabolism of transdermal preparations in Japan, multiple skin tissue specimens of individuals of Japanese descent were prepared, and the mRNA expression levels of CYP1A2, CYP3A4, and CYP3A5 were measured. Associations between the expression patterns of these CYPs and body mass index (BMI) were also investigated.There were considerable individual differences in epidermal CYP1A2 mRNA expression levels, and CYP1A2 showed a weak positive correlation with CYP3A4 mRNA expression levels. In contrast to previous results for other organs, epidermal CYP3A4 mRNA expression levels showed a weak positive correlation with BMI.CYP3A4 in the epidermis may have been locally enhanced as a defence mechanism against xenobiotics in response to impaired barrier function. These differences in mRNA expression in the skin may affect the transdermal absorption of drugs, such as lidocaine and fentanyl, which are metabolised by multiple overlapping CYPs.Our study provides new insights into drug metabolism in the skin. These results are valuable for predicting drug effects and transdermal drug transfer rates in Japanese patients.

Association Between Anxiety and Depressive Symptoms During Prehospitalization Waiting Period and Quality of Recovery at Postoperative Day 3 in Perioperative Cancer Patients.

PURPOSE: Perioperative depressive symptoms are associated with poor postoperative quality of life (QOL), leading to prolonged hospital stays, and delayed return to society. Previous studies show that physical and mental states change on the third day after surgery, and there is a correlation between quality of recovery (QoR) on this day and QOL at 3 months after surgery. QoR after surgery is an important indicator of postoperative QOL. However, there are no reports on the association between depressive symptoms, and postoperative QoR. Therefore, the study purpose was to clarify the relationship between depressive symptoms in perioperative cancer patients during the prehospitalization waiting period, and QoR on the third postoperative day. DESIGN: This was a prospective cohort study. METHODS: We examined whether depressive symptoms during the prehospitalization waiting period were related to QoR on day 3 after surgery in perioperative cancer patients. Subjects were patients with primary tumors who underwent surgery under general anesthesia. Subjects completed self-administered questionnaires during the prehospitalization waiting period and on postoperative day 3. The presence and/or absence of depressive symptoms was measured using the Hospital Anxiety and Depression Scale. Subjects were divided into two groups: depressive symptoms or non-depressive symptoms. Postoperative QoR was determined using the QoR-40 questionnaire and we calculated the rate of change in QoR-40 global and dimension scores from preoperation to postoperation. FINDINGS: 231 individuals met the inclusion criteria and agreed to participate in the study. Of these, 173 were included in the analysis. Only the rate of change in emotional state differed significantly between groups (P = .022). Both global and dimension QoR-40 scores were lower in the depressive symptoms group than in the non-depressive symptoms group. CONCLUSIONS: These findings demonstrate the need to provide both psychological and physical support continuously from the preoperative to early postoperative stage for cancer patients with depressive symptoms in the prehospitalization waiting period.

CRMP1 and CRMP2 have synergistic but distinct roles in dendritic development.

Collapsin response mediator protein 2, CRMP2, has been identified as an intracellular signaling mediator for Semaphorin 3A (Sema3A). CRMP2 plays a key role in axon guidance, dendritic morphogenesis, and cell polarization. It has been also implicated in a variety of neurological and psychiatric disorders. However, the in vivo functions of CRMP2 remain unknown. We generated CRMP2 gene-deficient (crmp2(-/-) ) mice. The crmp2(-/-) mice showed irregular development of dendritic spines in cortical neurons. The density of dendritic spines was reduced in the cortical layer V pyramidal neurons of crmp2(-/-) mice as well as in those of sema3A(-/-) and crmp1(-/-) mice. However, no abnormality was found in dendritic patterning in crmp2(-/-) compared to wild-type (WT) neurons. The level of CRMP1 was increased in crmp2(-/-) , but the level of CRMP2 was not altered in crmp1(-/-) compared to WT cortical brain lysates. Dendritic spine density and branching were reduced in double-heterozygous sema3A(+/-) ;crmp2(+/-) and sema3A(+/-) ;crmp1(+/-) mice. The phenotypic defects had no genetic interaction between crmp1 and crmp2. These findings suggest that both CRMP1 and CRMP2 mediate Sema3A signaling to regulate dendritic spine maturation and patterning, but through overlapping and distinct signaling pathways.

Reduction and fragmentation of elastic fibers in the skin of obese mice is associated with altered mRNA expression levels of fibrillin-1 and neprilysin.

AIM OF THE STUDY: Our previous research suggested that obesity induces structural fragility in the skin. Elastic fibers impart strength and elasticity. In this study, we determined whether elastic fibers decrease in the skin of obese mice. MATERIALS AND METHODS: To confirm alterations in elastic fiber content due to obesity, we used spontaneously obese model mice (TSOD) and control mice (TSNO). Furthermore, to evaluate the elastin structure and gene expression dependent on the severity of obesity, an obesity-enhanced mouse model was developed by feeding a high fat diet to TSOD (TSOD-HF). Back skin samples were stained with hematoxylin and eosin and Elastica van Gieson for microscopic examination, and the samples were stained for immunohistochemical analysis of neprilysin. Gene expression levels were determined using a real-time PCR system. RESULTS: The abundance of elastic fibers beneath the epidermis was remarkably reduced and fragmented in TSOD as compared with TSNO. Fibrillin-1 mRNA levels in TSOD were significantly suppressed compared with those in TSNO, whereas neprilysin mRNA levels and immunohistochemical expression in TSOD were significantly increased, as compared with those in TSNO. The reduction of elastic fibers was enhanced and the expression levels of elastic fiber formed factors were significantly suppressed in TSOD-HF, as compared with those in the TSOD. CONCLUSIONS: The abundance of elastic fibers was reduced and fragmented in obesity, suggesting that the reduction in elastic fibers is initially caused by increased neprilysin and decreased fibrillin-1 expression, which may inhibit formation and stabilization of elastic fibers, resulting in skin fragility in obesity.

Gallic Acid, the Active Ingredient of Terminalia bellirica, Enhances Adipocyte Differentiation and Adiponectin Secretion.

Visceral obesity induces the onset of metabolic disorders such as insulin resistance and diabetes mellitus. Adipose tissue is considered as a potential pharmacological target for treating metabolic disorders. The fruit of Terminalia bellirica is extensively used in Ayurvedic medicine to treat patients with diseases such as diabetes mellitus. We previously investigated the effects of a hot water extract of T. bellirica fruit (TB) on obesity and insulin resistance in spontaneously obese type 2 diabetic mice. To determine the active ingredients of TB and their molecular mechanisms, we focused on adipocyte differentiation using mouse 3T3-L1 cells, which are widely used to study adipocyte physiology. We show here that TB enhanced the differentiation of 3T3-L1 cells to mature adipocytes and that one of the active main components was identified as gallic acid. Gallic acid (10-30 µM) enhanced the expression and secretion of adiponectin via adipocyte differentiation and also that of fatty acid binding protein-4, which is the target of peroxisome proliferator-activated receptor gamma (PPARγ), although it does not alter the expression of the upstream genes PPARγ and CCAAT enhancer binding protein alpha. In the PPARγ ligand assay, the binding of gallic acid to PPARγ was undetectable. These findings indicate that gallic acid mediates the therapeutic effects of TB on metabolic disorders by regulating adipocyte differentiation. Therefore, TB shows promise as a candidate for preventing and treating patients with metabolic syndrome.

Oral Intake of Linseed Oil Inhibits Skin Barrier Dysfunction in Obese Mice.

OBJECTIVE: Obesity is not only a risk factor for lifestyle-related diseases but also causes skin barrier dysfunction, which leads to a reduced quality of life due to dryness, itching, and scratching, and thus requires appropriate treatment. However, there are no studies on this issue. Therefore, this study aimed to examine whether oral intake of linseed oil is effective for skin barrier function in obesity and to confirm how the effect is demonstrated. METHODS: TSOD mice received either sterile distilled water (Control group) or linseed oil (Omega group), containing a high level of omega-3 fatty acids, including α-linolenic acid, orally for eight weeks. Mice were then irradiated with ultraviolet B (UVB) and three days later, transepidermal water loss (TEWL), which is the primary outcome of skin barrier function, was measured and gross skin appearance was observed. Hematoxylin and eosin (HE) staining and Ki-67 immunostaining were performed on skin samples. mRNA expression levels of the inflammatory markers Tnfα, Cox2, Mcp1, and Hmox1 were measured by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). We also performed fatty acid analysis of skin and erythrocytes by gas chromatography. Statistical analysis was performed using unpaired Student's t-test and Pearson's correlation analysis. RESULTS: Compared with the Control group, the Omega group exhibited lower TEWL values and little skin erythema. Histological analysis revealed thinner epidermis and fewer Ki-67 positive cells. Additionally, in the Omega group, mRNA levels of four inflammation-related genes were lower, α-linolenic acid levels in both skin and erythrocytes were higher, and a lower n-6/n-3 ratio was observed. And α-linolenic acid levels in the skin were negatively correlated with the expression levels of inflammation-related genes. CONCLUSION: Oral intake of linseed oil was found to inhibit skin barrier dysfunction in obesity. This effect was mediated by α-linolenic acid, a major component of linseed oil with anti-inflammatory properties, which was taken up by erythrocytes and supplied to the skin. Therefore, oral intake of linseed oil is expected to be a useful therapeutic method for skin barrier dysfunction in obesity.

Identification of Drugs and Patient Profiles at Risk for Severe Skin Injuries Due to Extravasation: Analysis of a Spontaneous Reporting System.

This study aimed to identify risk factors and combinations thereof that are associated with severe skin injuries due to the extravasation of injectable drugs. A cross-sectional study using the Japanese Adverse Drug Event Report database was conducted according to the RECORD-PE checklist. Adverse event reports related to necrosis, ulcers, or erosions due to extravasation were considered "with severe skin injury," and others were considered "without severe skin injury." Approximately 255 cases "with" and 260 cases "without" severe skin injury were identified. The relationship between the incidence of severe skin injury and age, sex, drugs, and primary disease was evaluated using the χ2 test. Association rule mining was used to evaluate the correlation between each combination of factors and skin injury. Nine factors were identified as independent risk factors for severe skin injury, including age (<10 or ≥70 years), peripheral parenteral nutrition use, and mental disorders. The association rule mining results suggested that a combination of specific patient backgrounds and drug use was associated with the incidence of necrosis or ulcers. The findings of this study reiterate that nurses might consider closely observing patients with the risk factors identified in this study for the prevention and early detection of extravasation-related skin injuries.

Why and by How Much is Insulin Absorption Reduced by Insulin-derived Amyloidosis? A Scoping Review.

Insulin therapy is one of the central treatments for diabetes mellitus. Insulin-derived localized amyloidosis (IDLA) is a known skin-related complication of insulin injection. This is one of the causes of poor glycemic control in diabetic patients on insulin therapy. The aim of this study was to review and update the findings on the extent and mechanism of reduced insulin absorption in IDLA. A literature search was conducted on decreased insulin absorption and its mechanisms, and nine references were selected, with seven of these on decreased insulin absorption and four on mechanisms. Insulin absorption at IDLA sites was reported to be 27-94% lower compared with normal sites. In addition, a comparison between nonpalpable and palpable IDLA sites revealed a significant decrease in insulin absorption at the palpable IDLA site. The mechanism of insulin malabsorption was found to be a reduction in insulin absorption at the palpable IDLA sites. Four mechanisms of decreased insulin absorption were identified: decreased subcutaneous blood flow, adsorption of administered insulin onto insulin amyloid fibers, impaired diffusion of insulin subcutaneously, and physical factors such as shaking of the insulin preparation. These mechanisms should be investigated in vivo in the future.

Novel biomarkers for the detection of wound infection by wound fluid RT-PCR in rats.

Wound infection is a form of host damage resulting from an imbalance in pathogen virulence and the host immune response. However, at present, diagnosis is based solely on bacterial numbers or inflammatory signs and is therefore not precise. Thus, infection diagnosis requires indicators of both of these factors. We focused on wound fluid because it includes both bacteria and host cells. The purpose of this study was to establish biomarkers that reflect both bacterial and host factors using the reverse transcription-polymerase chain reaction method on the centrifugal precipitation of wound fluids (wound fluid RT-PCR). We created full thickness wounds in animal models of the three groups: control, colonization and infection, which were conditioned by administration of different concentrations of Pseudomonas aeruginosa dispersion. Messenger RNA expression in bacteria and host cells was analysed. Expression of bacterial housekeeping genes was detected in the samples in the colonization and infection groups. Expression of host housekeeping genes was detected in all samples from the three groups. Expression of toxA, encoding the virulence factor exotoxin A, was detected in 90% of samples in the infection group only. Expression of Foxp3, encoding the transcription factor forkhead box P3, was detected in 100% of samples only in the colonization group. These results revealed that wound fluid RT-PCR analysis reflected both bacterial virulence and the host immune status, and we determined the combination of novel biomarkers that can discriminate these three groups. We anticipate that wound fluid RT-PCR could be applied in the future to diagnose wound infection.

Skin fragility in obese diabetic mice: possible involvement of elevated oxidative stress and upregulation of matrix metalloproteinases.

The purpose of this study was to test the hypothesis that obese diabetic mice exhibit marked skin fragility, which is caused by increased oxidative stress and increased matrix metalloproteinase (MMP) gene expression in the subcutaneous adipose tissue. Scanning electron microscopy of skin samples from Tsumura-Suzuki obese diabetic (TSOD) mice revealed thinner collagen bundles, and decreased density and convolution of the collagen fibres. Furthermore, skin tensile strength measurements confirmed that the dorsal skin of TSOD mice was more fragile to tensile force than that of non-obese mice. The mRNA expressions of heme oxygenase 1 (Hmox1), a marker of oxidative stress, Mmp2 and Mmp14 were increased in the adipose tissue of TSOD mice. Antioxidant experiments were subsequently performed to determine whether the changes in collagen fibres and skin fragility were caused by oxidative stress. Strikingly, oral administration of the antioxidant dl-α-tocopherol acetate (vitamin E) decreased Hmox1, Mmp2 and Mmp14 mRNA expressions, and improved the skin tensile strength and structure of collagen fibres in TSOD mice. These findings suggest that the skin fragility in TSOD mice is associated with dermal collagen damage and weakened tensile strength, and that oxidative stress and MMP overexpression in the subcutaneous adipose tissue may, at least in part, affect dermal fragility via a paracrine pathway. These observations may contribute to novel clinical interventions, such as dietary supplementation with antioxidants or application of skin cream containing antioxidants, which may overcome skin fragility in obese patients with diabetes.

Novel models for bacterial colonization and infection of full-thickness wounds in rats.

An animal model is needed to study the pathophysiology of wound infections; however, an animal model that is reproducible and clinically relevant has not previously been available. In addition, an animal model of wound colonization generated in a manner similar to the wound infection model would be useful. Here, we describe new animal models of the wound infection continuum for the characterization of essential host-pathogen relationships. We determined the conditions needed to establish rat models of stable wound colonization and infection, without the use of disturbing factors (e.g., foreign bodies or induction of diabetes mellitus). We found that the age of the rats, bacterial inoculum size, and wound location were important elements in generating reproducible, obvious, spreading wound infections. We inoculated approximately 6-month-old rats with 2.06 × 10(9) or 4.12 × 10(9) colony-forming units of Pseudomonas aeruginosa to generate the wound colonization and wound infection models, respectively. Wounds were made 2 cm cranial to the greater trochanter. These clinically relevant and highly reproducible animal models can be used to investigate the mechanisms of wound infection and monitor the effect of therapeutic agents in vivo.

Preventive Effect of Boiogito on Metabolic Disorders in the TSOD Mouse, a Model of Spontaneous Obese Type II Diabetes Mellitus.

"Boiogito" is a Kampo preparation which has been used since ancient times in patients with obesity of the "asthenic constitution" type, so-called "watery obesity", and its effect has been recognized clinically. In this study, we investigated the anti-obesity effect of Boiogito in the TSOD (Tsumura Suzuki Obese Diabetes) mouse, a model of spontaneous obese type II diabetes mellitus. Boiogito showed a significant anti-obesity effect in TSOD mice by suppressing body weight gain in a dosage-dependent manner. In addition, Boiogito showed significant ameliorative effects on features of metabolic syndrome such as hyperinsulinemia, fasting hyperglycemia and abnormal lipid metabolism. Regarding lipid accumulation in TSOD mice, Boiogito showed a significant suppressive effect on accumulation of subcutaneous fat, but the effect on the visceral fat accumulation that constitutes the basis of metabolic syndrome was weak, and the suppressive effect on insulin resistance was also weak. Furthermore, Boiogito did not alleviate the abnormal glucose tolerance, the hypertension or the peripheral neuropathy characteristically developed in the TSOD mice. In contrast, in the TSNO (Tsumura Suzuki Non-Obesity) mice used as controls, Boiogito suppressed body weight gain and accumulation of subcutaneous and visceral fat. The above results suggested that Boiogito is effective as an anti-obesity drug against obesity of the "asthenic constitution" type in which subcutaneous fat accumulates, but cannot be expected to exert a preventive effect against various symptoms of metabolic syndrome that are based on visceral fat accumulation.

Preventive Effects of Salacia reticulata on Obesity and Metabolic Disorders in TSOD Mice.

The extracts of Salacia reticulata (Salacia extract), a plant that has been used for the treatment of early diabetes, rheumatism and gonorrhea in Ayurveda, have been shown to have an anti-obesity effect and suppress hyperglycemia. In this study, the effects of Salacia extract on various symptoms of metabolic disorder were investigated and compared using these TSOD mice and non-obese TSNO mice. Body weight, food intake, plasma biochemistry, visceral and subcutaneous fat (X-ray and CT), glucose tolerance, blood pressure and pain tolerance were measured, and histopathological examination of the liver was carried out. A significant dose-dependent decline in the gain in body weight, accumulation of visceral and subcutaneous fat and an improvement of abnormal glucose tolerance, hypertension and peripheral neuropathy were noticed in TSOD mice. In addition, hepatocellular swelling, fatty degeneration of hepatocytes, inflammatory cell infiltration and single-cell necrosis were observed on histopathological examination of the liver in TSOD mice. Salacia extract markedly improved these symptoms upon treatment. Based on the above results, it is concluded that Salacia extract has remarkable potential to prevent obesity and associated metabolic disorders including the development of metabolic syndrome.

[Pharmacology education in nursing degree course in order to cultivate nurses skilled in drug therapy].

In nursing degree course education, it is needed to enhance contents of pharmacology education for acquiring nursing practice ability in the nursing education model core curriculum and revision of designation regulations. Therefore, it is intended to consider pharmacology education in nursing degree course in universities in the current study in order to cultivate nurses skilled in drug therapy. We have conducted a survey on knowledge required for students of universities of nursing as well as an analysis on contents of inquiries made by nurses on drugs. As a result, it has been revealed that students have recognized effect and side effects of drugs as basic knowledge required for a nurse. With less recognition required on pharmacokinetics and practical contents, however, the knowledge held by students was dissociated with practical knowledge often required for nurses when administering drugs. A possibility has been also revealed by the current survey that nurses may not be able to make use of pharmacokinetics as pharmacological knowledge for patients' treatment management. From results of the survey and previous study, it is believed to be necessary in university education to extend pharmacological knowledge from its basic to clinical stage and build up adequate basic knowledge and thinking power of pharmacology in nursing degree course as well as to sufficiently learn and understand necessity of pharmacokinetics for conducting evaluation of drug efficacy.

Candidate biomarkers for deep tissue damage from molecular biological and biochemical aspects.

Suspected deep tissue injury (DTI) is a new category of pressure ulcer (PU), and defined as an ulcer that developed from a deep tissue (subcutaneous tissue) region and deteriorates towards the superficial skin. DTI is a serious clinical problem because it cannot be detected at an early stage and rapidly deteriorates to a deep PU. Consequently, there is a requirement for the identification of novel biomarkers to detect damage to the deep tissue including deep muscle tissue. For this purpose, it is essential to understand the molecular and cellular mechanisms of DTI formation and deterioration. This article reviews the recent progress in studies on the hypoxia-related mechanisms of DTI, and introduces our attempts to establish novel biomarkers for detecting deep muscle damage. Hypoxia-inducible factor 1 alpha subunit (HIF1-alpha) is a widely used marker for hypoxic conditions. We detected increased expression and localization of HIF1-alpha in the deep muscle tissue of PU model rats, indicating that HIF1alpha is a key molecule in DTI and a valuable biomarker for hypoxia in DTI in the research field. From the biochemical aspect, we focused on creatine phosphokinase (CPK). CPK is an intracellular enzyme related to energy metabolism, and its level in serum has been extensively used as a diagnostic marker for muscle injury. We attempted to estimate muscle injury from the CPK levels in exudates, which can be collected non-invasively and reflect the microenvironmental conditions. Our results using PU model rats suggested that exudate CPK could be a more sensitive biomarker than serum CPK for deep muscle tissue injury, and could be applicable for clinical diagnosis of DTI.

Hypoxia is Involved in Deep Tissue Injury Formation in a Rat Model .

Abstract: Pressure ulcers that develop from deep tissue are known as deep tissue injuries (DTI). Although several mechanisms, including ischemic hypoxia, are attributed to pressure ulcer formation, the mechanisms involved in DTI formation are still unclear. Previous studies have suggested that hypoxia is involved in DTI in vitro, but it has yet to be determined whether hypoxia is also involved in DTI in vivo. Therefore, this study aimed to investigate whether hypoxia is involved in DTI using a newly established DTI model. Rats were divided into control, low pressure DTI, and high pressure DTI groups. Results of wound healing tests indicated that more severe DTI resulted in prolonged healing time, more severe inflammation and muscle damage, higher levels of exudate creatine phosphokinase, and greater muscle edema. Increased hypoxia was observed in severe DTI-nuclear localization of hypoxia-inducible factor-1α was markedly increased in the high pressure DTI group, while the low pressure group showed more increased cytoplasm localization compared to the control group on day 3. Study results revealed that hypoxia is involved in DTI in vivo.

[Single center survey of the relationship between pregnancy anemia and prepregnancy lifestyle].

Physiologically, anemia often occurs during pregnancy because of an increase in circulating plasma volume. Pregnancy anemia is found prenatally in 50-75% of women. Based on the present survey performed in our obstetrics and gynecology ward, 52% of women experienced anemia during their pregnancy. This suggests that normal physiological changes due to pregnancy alone are not the only factors contributing to pregnancy anemia. Therefore to study the influence of lifestyle on pregnancy anemia, we investigated prepregnancy lifestyles on the assumption that the accumulation of several factors over a long period is usually the cause of anemia. The present results suggest that (i) the probability of anemia is slight in late pregnancy, if a normal Hb concentration is maintained in early pregnancy; (ii) the menstrual cycle is involved in the onset of anemia during early pregnancy; (iii) the number of meals taken and the level of alcohol consumption influence Hb concentration in late pregnancy. We believe that these findings provide a useful information source for advising patients on avoiding pregnancy anemia, which we can also use as guidance for outpatients at puberty. In conclusion, to prevent pregnancy anemia it is important to keep a regular menstrual cycle before pregnancy, and to take 3 meals/day and abstain from alcohol before and during pregnancy.

[Pharmacology education in nursing: what should be taught and how? - from Western to Chinese medicine].

Doctors give prescriptions after considering the medical conditions of patients. Pharmacists check the prescription and give information about the effects of the drugs to the patients, including their side effects. Nurses observe patients to determine the effects and side effects of the administered drugs, and then report these to doctors. Each specialist plays a role, allowing medication to be completed. However, in order to fully attain the effects of a drug, we need to consider the method of its administration. For example, it is difficult to attain the effects of laxatives for a person who eats irregularly; however, they are uniformly administered. Pharmacology education in nursing focuses on the mechanism of drugs and the way of maintaining their therapeutic effects and safeness, based on the viewpoint of "curing". Furthermore, nursing science focuses on the differences in efficacy depending on the characteristics of a patient, and also on the side effects of drugs, based on the viewpoint of "caring". However, education where care and cure are integrated needs to be provided, so that nurses can acquire applied skills to consider individual patient's bodies, lives, and psychological situations comprehensively, and then suggest the optimal method of administration. Also, there is Eastern medicine as well as Western medicine. Administration of Chinese medicine should be related to the patient's lifestyle. Nurses have to learn how each medicine is related to the patient's lifestyle, and what aspects in the patient they have to focus on.

Aging-like physiological changes in the skin of Japanese obese diabetic patients.

OBJECTIVE: Obesity-associated diabetes causes aging-like changes to skin physiology in animal models, but there have been no clinical studies focusing on human obese diabetic patients. The purpose of this study was to examine the hypothesis that obesity-associated diabetes accelerates aging-like skin changes in Japanese people. METHODS: This cross-sectional study enrolled obese-diabetes patients (body mass index ≥ 25 kg m-2) and healthy volunteers (body mass index < 25 kg m-2) as controls. Skin physiology parameters relating to aging (stratum corneum hydration, transepidermal water loss, skin pH, advanced glycation end-products, and dermal collagen density) were evaluated in the two groups. RESULTS: About 37 subjects participated (16 in a control group and 21 in an obese-diabetes group). Age was not significantly different between the groups. The stratum corneum hydration level was significantly lower in the obese-diabetes group. Transepidermal water loss and levels of advanced glycation end-products were significantly higher in this group. Skin pH was not significantly different between groups. Dermal collagen density decreased in the obese-diabetes group. CONCLUSION: We showed that obese-diabetes patients have decreased stratum corneum hydration, increased transepidermal water loss, higher skin advanced glycation end-products and decreased dermal collagen fiber density compared with normal-weight subjects. These results indicate that the ordinary age-related physiological skin changes seen in the elderly can also occur in obese-diabetes patients aged in their 40s.

Reduced skin lipid content in obese Japanese women mediated by decreased expression of rate-limiting lipogenic enzymes.

Skin barrier function is often deficient in obese individuals, but the underlying molecular mechanisms remain unclear. This study investigated how skin structure and lipid metabolism, factors strongly associated with barrier function, differed among 50 Japanese women of greatly varying body mass index (BMI). Subjects receiving breast reconstruction surgery were chosen for analysis to obtain skin samples from the same site. The subjects were classified into two groups, control (BMI < 25 kg/m2) and obese (25 kg/m2 ≤ BMI < 35 kg/m2), according to standards in Japan. Hematoxylin and eosin staining was used to assess skin thickness, Ki-67 immunostaining to examine keratinocyte proliferation, and real-time polymerase chain reaction to measure skin expression levels of genes associated with lipid metabolism. Total lipids, cholesterol, and fatty acids were also measured from these same skin samples. In the obese group, structural changes included epidermal thickening and an increase in the number of Ki-67-positive (proliferating) cells. Both skin cholesterol and fatty acid levels exhibited an "inverted-U" relationship with BMI, suggesting that there is an optimal BMI for peak lipid content and barrier function. Decreased lipid levels at higher BMI were accompanied by downregulated expression of PPARδ and other genes related to lipid metabolism, including those encoding acetyl-CoA carboxylase and HMG-CoA reductase, the rate-limiting enzymes for fatty acid and cholesterol synthesis, respectively. Thus, elevated BMI may lead to deficient skin barrier function by suppressing local lipid synthesis.