Certolizumab pegol effectiveness, survival and safety in patients with psoriasis: A multicenter retrospective analysis in daily clinical practice by the Spanish Psoriasis Group.

BACKGROUND: Certolizumab is an Fc-free PEGylated tumor necrosis factor-alpha (TNFα) inhibitor recently approved for the treatment of moderate-to-severe plaque psoriasis, although there is limited real-world evidence on the effectiveness and safety in patients with plaque psoriasis treated with certolizumab. The objective of this article is to determine the effectiveness, drug survival, and safety, including pregnancy, childbirth, and lactation, of certolizumab in moderate-to-severe plaque psoriasis under real-world conditions. METHODS: This is a retrospective, multicenter, observational study performed in 15 hospitals in Spain. It evaluates the effectiveness and safety of certolizumab in plaque psoriasis in the clinical practice setting. RESULTS: A total of 67 patients (73% female) were evaluated with a mean baseline Psoriasis Area Severity Index (PASI) of 8.9. At Week 12, the mean PASI was 2.3 (n = 67), 1.3 (n = 57) at Week 24 and 1.3 at Week 52 (n = 34). Absolute PASI < 3 was achieved in 69, 86, and 92% of patients at Weeks 12, 24, and 52, respectively, as observed. For its part, using the under-response imputation analysis, PASI < 3 at Weeks 12, 24, and 52 were achieved by 69, 73, and 49% of the patients, respectively. A total of 35 patients (52%) had concomitant psoriatic arthritis, and, in 24 of them, Disease Activity in Psoriatic Arthritis Score (DAPSA) was recorded at baseline, with a mean value of 17.9 which decreased to 8.2 at Week 12 (n = 22) and to 3.6 at Week 24 (n = 18). Certolizumab treatment was discontinued in 14 out of 67 patients (21%), due to lack/loss of cutaneous or articular effectiveness (n = 11) or patient decision (n = 2) or adverse event in only one patient who developed active tuberculosis. A lower baseline PASI [hazard ratio (HR): 1.12 (1.02-1.23); P = 0.023] and a more significant reduction in PASI at Week 12 [HR: 1.16 (1.07-1.27); P < 0.001] and Week 52 [HR: 1.47 (1.11-1.96); P = 0.007] was shown to be significantly related with better survival for the entire follow-up period. Fourteen patients were treated during pregnancy and/or lactation without reporting adverse events in either the patient or the newborn. CONCLUSIONS: Certolizumab consistently showed high effectiveness and drug survival rates in this real-life cohort. The safety demonstrated in clinical trials during pregnancy and lactation seems to be confirmed in clinical practice.

Patch Testing in Patients With Severe Atopic Dermatitis Treated With Dupilumab: A Multicentric Approach in Spain.

Background: Persistent localized dermatitis (PLD) or eczema flare-ups (EF) may occur in atopic dermatitis (AD) patients treated with dupilumab. They may reflect concomitant allergic contact dermatitis (ACD) exposed by the inhibition of the Th2 pathway by dupilumab in some cases. Objective: To evaluate the prevalence and etiology of these events and the impact of dupilumab on patch test outcome. Methods: We performed patch tests on 54 AD patients treated with dupilumab and evaluated the prevalence and final diagnosis of EF and PLD as well as the patch test results. Results: The patch test results were positive in 20/54 (37.0%). 21/54 patients (38.9%) had PLD and 12/54 (22.2%) had EF. Ten of 54 (18.5%) had both conditions and 11/54 (20.4%) had neither PLD nor EF. 64.5% of PLD involved the face. 83.9% patients with PLD and 90.9% patients with EF were diagnosed with inadequately controlled AD. 9.7% patients with PLD and 4.5% patients with EF were finally diagnosed with ACD. Nine of 21 (42.9%) patients patch tested twice were positive either before and/or during dupilumab. Patch tests results changed over time in all of them. Conclusions: Patch testing assisted us to exclude ACD as the cause of PLD/EF in AD patients treated with dupilumab. Most PLD and EF were, however, diagnosed as poorly controlled AD. Dupilumab appeared to impact the patch test outcomes.

Cardiovascular Screening Practices and Statin Prescription Habits in Patients with Psoriasis among Dermatologists, Rheumatologists and Primary Care Physicians.

Patients with psoriasis have a higher prevalence of cardiovascular risk factors. This study evaluated cardiovascular screening practices and statin prescribing habits among dermatologists, rheumatologists and primary care physicians (PCPs) through an online questionnaire, which was distributed through the Spanish scientific societies of the above-mentioned specialties. A total of 299 physicians (103 dermatologists, 94 rheumatologists and 102 PCPs) responded to the questionnaire. Of these, 74.6% reported screening for smoking, 37.8% for hypertension, 80.3% for dyslipidaemia, and 79.6% for diabetes mellitus. Notably, only 28.4% performed global screening, defined as screening for smoking, hypertension, dyslipidaemia, and diabetes mellitus by the same physician, and 24.4% reported calculating 10-year cardiovascular disease (CVD) risk, probably reflecting a lack of comprehensive cardiovascular risk assessment in these patients. This study also identified unmet needs for awareness of cardiovascular comorbidities in psoriasis and corresponding screening and treatment recommendations among PCPs. Of PCPs, 61.2% reported not being aware of the association between psoriasis and CVD and/or not being aware of its screening recommendations, and 67.6% did not consider psoriasis as a risk-enhancing factor when deciding on statin prescription. Thirteen dermatologists (12.6%) and 35 rheumatologists (37.2%) reported prescribing statins. Among those who do not prescribe, 49.7% would be willing to start their prescription.

Guselkumab effectiveness and survival in patients with psoriasis and psoriatic arthritis: Multicenter analysis in daily clinical practice by the Spanish Psoriasis Group.

Guselkumab is a monoclonal antibody that selectively blocks the p19 subunit of interleukin 23 and has been approved for the treatment of moderate to severe psoriasis and active psoriatic arthritis in adult patients due to its efficacy in different clinical trials. Therefore, itis important to know the performance of guselkumab in this setting of patients in clinical practice given that a high percentage of them are not represented in these clinical trials. Our objective was to evaluate the effectiveness and tolerability of guselkumab in clinical practice in the first patients with psoriasis and psoriatic arthritis treated since the date of its approval for psoriasis in Spain, in joint dermatology-rheumatology clinics. A multicenter retrospective data collection was carried out, in which 14 hospitals participated, including a total of 90 patients with psoriatic arthritis confirmed by a rheumatologist. Data collection was recorded at baseline and at weeks 12, 24, and 52 for both the articular and cutaneous domains. Ninety PsA patients started treatment with guselkumab and therefore were included in this study. The vast majority had already failed to at least to one biologic therapyprior guselkumab prescription. The median age was 55 years, 61% were female and 46% had a BMI ≥ 30 kg/m2 . Sixty-nine percent suffered from peripheral arthritis, and in 34% an axial involvement was also detected; dactylitis or enthesitis was present in 24% and 29% of patients, respectively. Guselkumab was effective in controlling both articular and skin manifestations of PsA patients. Absolute PASI significantly decreased from 10.5 to 4.8, 1.9 and 1.3 at weeks 12, 24, and 52, respectively. In 29 out of 61 (48%) of cases, DAPSA was moderate or high, and patients showed a significant reduction in DAPSA at 12, 24, and 52 weeks of treatment (mean DAPSA values at baseline and follow up were 29, 20, 16, and 14, respectively). Patients with DAPSA in low activity or in remission at the time of initiation of guselkumab maintained response at the end of the study period. No new safety concerns were detected. Seventy-eight out of 90 patients (84.4%) persisted on treatment after 2 years follow-up. Our experience suggests that guselkumab isan effective drug for PsA and PsO patients in clinical practice with good tolerability and no additional safety signals, making it a new therapeutic alternative for the treatment of PsA and PsO patients.

Drug Survival of IL-12/23, IL-17 and IL-23 Inhibitors for Psoriasis Treatment: A Retrospective Multi-Country, Multicentric Cohort Study.

BACKGROUND: Drug survival analysis of biologic agents in psoriasis is of extreme importance, as it allows not only the evaluation of objective clinical outcomes (such as effectiveness and safety) but also of factors that are associated with patients' adherence to treatment. The aim of this study was to evaluate and compare the drug survival of the most recent biologic agents approved for the treatment of moderate-to-severe psoriasis-ustekinumab, secukinumab, ixekizumab, brodalumab, guselkumab, and risankizumab-and to identify clinical predictors that can influence the drug survival of these drugs. METHODS: This retrospective multicentric cohort study from 16 dermatology centers in Portugal, Spain, Italy, Switzerland, Czech Republic, Canada, and the United States included patients that started IL-12/23, IL-17 (IL-17A and IL-17R) and IL-23 inhibitors for the treatment of psoriasis between January 1, 2012 and December 31, 2019. Survival analysis was performed using a Kaplan-Meier estimator, to obtain descriptive survival curves, and proportional hazard Cox regression models. RESULTS: A total of 3312 treatment courses (total patients: 3145) were included in the study; 1118 (33.8%) with an IL-12/23 inhibitor (ustekinumab), 1678 (50.7%) with an IL-17 inhibitor [911 (27.5%) on secukinumab, 651 (19.7%) on ixekizumab, 116 (3.5%) on brodalumab], and 516 (15.5%) with an IL-23 inhibitor [398 (12.0%) on guselkumab, 118 (3.5%) on risankizumab]. At 18 months, the cumulative probability of survival was 96.4% for risankizumab, 91.1% for guselkumab, 86.3% for brodalumab, 86.1% for ustekinumab, 82.0% for ixekizumab, and 79.9% for secukinumab. Using ustekinumab as reference, drug survival of guselkumab was higher (HR 0.609; 95% CI 0.418-0.887) and that of secukinumab was lower (HR 1.490; 95% CI 1.257-1.766). In the final multivariable model, secukinumab, female sex, higher BMI, and prior exposure to biologic agents significantly increased the risk of drug discontinuation, whereas risankizumab was protective. CONCLUSION: In this multinational cohort with 8439 patient-years of follow-up, the cumulative probability of drug survival for all drugs was >79% at 18 months. Prescribed biologic, female sex, higher BMI, and previous exposure to biologic agents were predictors of drug discontinuation. Drug survival of guselkumab and risankizumab was higher than that of ustekinumab, and secukinumab was lower.

Frequency of sensitization to the individual fragrances of fragrance mix I and II according to the factors included in the MOAHLFA index.

BACKGROUND: Fragrances constitute the second most frequent cause of allergic contact dermatitis in Spain. OBJECTIVES: To determine the rate of sensitization to the individual fragrances of fragrance mix (FM) I and FM II for each of the demographic and clinical factors included in the MOAHLFA (male, occupational dermatitis, atopic dermatitis, hand dermatitis, leg dermatitis, facial dermatitis, age) index. METHODS: We conducted a 5-year retrospective study in 23 Spanish centres. We identified the patients who had undergone patch testing with a specific fragrance series after reacting positively to fragrance markers in a baseline series. We obtained the MOAHLFA index items in this population, then calculated for each demographic and clinical factor the frequencies of sensitization to the individual fragrances of FM I and FM II. RESULTS: A specific fragrance series was patch tested in 1013 patients. The most frequent allergens in men, women, children, and retired people were Evernia prunastri (16%), geraniol (16.6%), isoeugenol (17.9%), and geraniol (22.4%), respectively. Citral (20.5%) and hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) (14.5%) were the most common allergens in occupational eczemas and were also associated with a large proportion of hand and facial dermatitis. CONCLUSIONS: Frequency of sensitization to the individual fragrances of FM I and FM II varies with age, sex, affected body region, and history of occupational or atopic dermatitis.

Effect of Sex in Systemic Psoriasis Therapy: Differences in Prescription, Effectiveness and Safety in the BIOBADADERM Prospective Cohort.

The effect of sex on systemic therapy for psoriasis has not been well studied. The aim of this study was to analyse a large multicentre Spanish cohort of 2,881 patients with psoriasis (58.3% males), followed from January 2008 to November 2018, to determine whether sex influences prescription, effectiveness of therapy, and the risk of adverse events. The results show that women are more likely than men to be prescribed biologics. There were no differences between men and women in effectiveness of therapy, measured in terms of drug survival. Women were more likely to develop adverse events, but the difference in risk was small and does not justify different management. Study limitations include residual confounding and the use of drug survival as a proxy for effectiveness.

Aging in Male Wistar Rats Associates With Changes in Intestinal Microbiota, Gut Structure, and Cholecystokinin-Mediated Gut-Brain Axis Function.

Aging in mammals is characterized by failure of the homeostatic mechanisms that regulate energy balance. Several mechanisms have been proposed such as the presence of a low-grade chronic inflammation in different tissues, as well as leptin and insulin resistance, but the primary alteration is not fully elucidated. The gut microbiota has recently emerged as a key player in a variety of metabolic and neurological disorders. A main concept in this context is the gut-brain axis that refers to alterations in the gut that mediate effects in the central nervous system, including those related with the control of energy balance. Using 16S rRNA analysis, we demonstrate that aged male Wistar rats have increased presence of mucin-degrading and lipopolysaccharide (LPS)-producing bacteria. In addition, old animals exhibit a lower number of neutral mucin secreting goblet cells, and a decrease of tight junctions and adherens junctions marker proteins, zonula occludens protein-1 (ZO-1) and ß-catenin, respectively. These data are compatible with a thinner mucus layer and a weaker gut barrier in older animals that likely facilitate LPS leakage. Our data also show that cholecystokinin (CCK) satiating effect is impaired in aged rats, one of the expected effects of increased LPS leakage. In contrast, no overt signs of gut or systemic inflammation are observed. Changes in microbiota in old male Wistar rats present features of situations of increased adiposity, but different from those of obese animals. These could partly explain the increased adiposity and fat deposition in liver and heart as observed here.

Impact of global PTP1B deficiency on the gut barrier permeability during NASH in mice.

OBJECTIVE: Non-alcoholic steatohepatitis (NASH) is characterized by a robust pro-inflammatory component at both hepatic and systemic levels together with a disease-specific gut microbiome signature. Protein tyrosine phosphatase 1 B (PTP1B) plays distinct roles in non-immune and immune cells, in the latter inhibiting pro-inflammatory signaling cascades. In this study, we have explored the role of PTP1B in the composition of gut microbiota and gut barrier dynamics in methionine and choline-deficient (MCD) diet-induced NASH in mice. METHODS: Gut features and barrier permeability were characterized in wild-type (PTP1B WT) and PTP1B-deficient knockout (PTP1B KO) mice fed a chow or methionine/choline-deficient (MCD) diet for 4 weeks. The impact of inflammation was studied in intestinal epithelial and enteroendocrine cells. The secretion of GLP-1 was evaluated in primary colonic cultures and plasma of mice. RESULTS: We found that a shift in the gut microbiota shape, disruption of gut barrier function, higher levels of serum bile acids, and decreased circulating glucagon-like peptide (GLP)-1 are features during NASH. Surprisingly, despite the pro-inflammatory phenotype of global PTP1B-deficient mice, they were partly protected against the alterations in gut microbiota composition during NASH and presented better gut barrier integrity and less permeability under this pathological condition. These effects concurred with higher colonic mucosal inflammation, decreased serum bile acids, and protection against the decrease in circulating GLP-1 levels during NASH compared with their WT counterparts together with increased expression of GLP-2-sensitive genes in the gut. At the molecular level, stimulation of enteroendocrine STC-1 cells with a pro-inflammatory conditioned medium (CM) from lipopolysaccharide (LPS)-stimulated macrophages triggered pro-inflammatory signaling cascades that were further exacerbated by a PTP1B inhibitor. Likewise, the pro-inflammatory CM induced GLP-1 secretion in primary colonic cultures, an effect augmented by PTP1B inhibition. CONCLUSION: Altogether our results have unraveled a potential role of PTP1B in the gut-liver axis during NASH, likely mediated by increased sensitivity to GLPs, with potential therapeutic value.

Effectiveness and safety of ustekinumab 90 mg in patients weighing 100 kg or less: a retrospective, observational, multicenter study.

Background: Scant information from clinical practice is available on the effectiveness and safety of ustekinumab (UST) 90 mg in patients with psoriasis weighing 100 kg or less.Objectives: To assess the effectiveness and safety at weeks 16 and 24 of UST 90 mg in patients with psoriasis weighing ≤100 kg, and to study the impact on clinical outcomes of body mass index (BMI) and prior exposure to UST 45 mg.Methods: A retrospective, observational, and multicenter study of 74 adult patients who were treated with UST 90 mg at least 24 weeks.Results: Mean (standard deviation [SD]) score on psoriasis area and severity index (PASI) was 7.9 (4.8) at baseline, 3.3 (3.5) at week 16, and 2.2 (2.4) at week 24, when 69.7% of the patients had a PASI under 3. Overweight and obese patients achieved a mean PASI of 2.2 by week 24 (p= .995). In patients who had previously been treated with UST 45 mg (52/74) with insufficient response, mean (SD) absolute PASI score was 2.7 (2.6) at week 24. No serious adverse events were reported.Conclusions: In patients who weigh 100 kg or less but are overweight or obese and do not present an adequate response with UST 45 mg, increasing the dose to UST 90 mg could be an alternative option.

Sensitization to fragrances in Spain: A 5-year multicentre study (2011-2015).

BACKGROUND: Fragrance chemicals constitute the second most frequent cause of contact allergy in Spain. There are no data available concerning the individual fragrances that are most frequently involved. OBJECTIVES: To describe the diagnostic contribution provided by specific fragrance series to the results obtained with baseline series fragrance markers by correlating the results of both series. MATERIALS AND METHODS: We performed a 5-year retrospective study of fragrance marker-positive patients tested with specific fragrance series in 23 Spanish centres. We collected the demographic and clinical characteristics, and compared the results of patch tests obtained from different suppliers. RESULTS: Of 19 588 patients patch tested with the Spanish baseline series, 1590 (8.1%) reacted positively to a fragrance marker. Of these, 1013 (63.7%) were patch tested with a fragrance series, and 664 patients reacted positively to at least one individual fragrance other than hydroxyisohexyl 3-cyclohexene carboxaldehyde. Geraniol was the most frequent allergen. Positive reactions to substances not included in fragrance mix (FM) I or FM II were found in 230 patients. Of the 436 FM I-positive patients and the 419 FM II-positive patients, 184 (42%) and 64 (39.1%), respectively, had no positive reactions to fragrance series. In the case of FM I, negative results were more common when individual fragrances were patch tested at low concentrations. CONCLUSIONS: We recommend patch testing all patients positive for any fragrance marker with a specific fragrance series. The correlation between the results of baseline series and fragrance series could be improved by increasing the concentrations of individual fragrances.

Toll-like receptor 9 promoter polymorphism as a predictive factor of narrow-band UVB phototherapy response in patients with psoriasis.

BACKGROUND: Prediction of response to ultraviolet B (UVB) phototherapy in psoriatic patients mainly relies on clinical criteria, although some genetic predictors have been identified. Toll-like receptors (TLRs) have been involved in psoriasis pathogenesis through activation of the innate immune system. Their polymorphisms may condition not only the clinical profile of psoriasis but also the response to therapy. METHODS: We analyzed the role of functional single-nucleotide polymorphisms (SNPs) of TLR2, 5, 4, and 9 in clinical response to a standard narrow-band UVB (NBUVB) therapy in 39 patients with moderate to severe psoriasis. RESULTS: We found a significant relationship between TLR9-1486T/C SNP variants and a better response to NBUVB phototherapy. Patients with TC and CC genotype showed a higher improvement of Psoriasis Area and Severity Index (PASI) than patients with TT genotype. Results of multivariate analysis indicate that the differences in PASI improvement at the end of phototherapy attributed to TRL9 SNP genotype were not dependent on the patients' phototype, age, gender, body mass index, basal PASI, or disease evolution. CONCLUSIONS: We describe a functional genetic variant in TLR9 gene that might affect the susceptibility to antipsoriatic treatment. The search of genetic predictive factors may be helpful in therapy selection and optimization of therapeutic regimes in psoriatic patients.

Effects of age and caloric restriction on the cardiac and coronary response to endothelin-1 in rats.

BACKGROUND AND AIMS: Aging is associated with alterations in the cardiovascular system such as increased vasoconstriction and decreased vasodilatation. Some of these changes are partially reversed by caloric restriction. Endothelin-1 is a potent vasoconstrictor which levels increased with age. The aim of this study is to analyze the role of endothelin-1 in the cardiac and coronary changes induced by age and whether these changes may be attenuated by a three-month caloric restriction. METHODS AND RESULTS: Hearts from young (3 months old), aged (24 months old) and aged rats after 3 months of caloric restriction were perfused according to the Langendorff technique. Coronary vasoconstriction to endothelin-1 was reduced in old rats, and endothelin-1 increased myocardial contractility (dP/dt) and heart rate in old but not in young rats. These changes observed in old rats were partly reversed by caloric restriction. Also, in the myocardial tissue of old rats the gene expression of endothelin-1, inducible nitric oxide synthase (iNOS) and tumor necrosis factor alpha (TNF-a) was increased, and the gene expression of endothelin ETB receptors and endothelial nitric oxide syntase (eNOS) was reduced, compared with young rats. Aging induced changes in the expression of ETB receptors and eNOS were reversed by caloric restriction. CONCLUSIONS: These results suggest that aging produces alterations in myocardial and coronary responses to endothelin-1, that may be related to changes in expression of nitric oxide synthases and/or endothelin receptor subtypes, with some of these changes being prevented by caloric restriction.

Cardiovascular risk factors and cardiovascular diseases in patients with moderate to severe psoriasis under systemic treatment. PSO-RISK, descriptive study.

BACKGROUND: The prevalence of cardiovascular risk factors (CVRF) in psoriasis has not been studied in large Spanish samples. OBJECTIVE: To assess the prevalence of major CVRFs in psoriasis patients requiring systemic treatments. MATERIAL AND METHODS: Cross-sectional study in psoriasis patients from 33 hospital dermatology offices throughout Spain. Blood pressure (BP) was measured and a fasting lab test was performed. Each CVRF was diagnosed according to the recommendations of international societies. RESULTS: In 368 patients (mean age 48 years old, 36% women), 80.2% had at least one CVRF. The prevalence of each CVRF was similar in men and women and slightly higher in patients with psoriatic arthritis and in patients with a history of more severe disease. The percentage of patients treated with drugs to control CVRF was low (∼ 50% of those with each CVRF). A total of 20.7% had experienced some cardiovascular disease (CVD) episode. CONCLUSION: The prevalence of CVRF was high, higher than in the general Spanish population, and 20% had already suffered CVD. However, the percentage with drug treatments for CVRF was low.

Impairment of skeletal muscle insulin action with aging in Wistar rats: role of leptin and caloric restriction.

Insulin resistance develops with aging in rats in parallel to fat mass accretion, central leptin resistance and hyperleptinemia. Previous studies demonstrated that insulin resistance appears earlier in adipose tissue than in muscle during aging and pointed to a role of hyperleptinemia in the impairment of insulin action. Here we explored the evolution along aging of insulin sensitivity in soleus and EDL muscles by analyzing insulin signaling in vivo and insulin-dependent glucose transport ex vivo. A decrease in insulin action was observed in both muscles. Caloric restriction improves insulin sensitivity at early aging but not in older animals. We also tested the role of leptin on insulin action in skeletal muscle. Short-term pretreatment with leptin inhibits in vivo muscle insulin signaling and insulin-dependent glucose transport in isolated muscle strips. This effect is mediated by its action on early insulin signaling as well as by the inhibition of p38. In contrast, chronic central administration of leptin elicits an insulin sensitizing effect on soleus. These data suggest that leptin can act as muscle insulin sensitizer, when acting at central level, and as insulin antagonistic when interacting directly with soleus muscle. This effect may be relevant in situations of hyperleptinemia such as aging.

Essential role of protein tyrosine phosphatase 1B in obesity-induced inflammation and peripheral insulin resistance during aging.

Protein tyrosine phosphatase 1B (PTP1B) is a negative regulator of insulin signaling and a therapeutic target for type 2 diabetes (T2DM). In this study, we have evaluated the role of PTP1B in the development of aging-associated obesity, inflammation, and peripheral insulin resistance by assessing metabolic parameters at 3 and 16 months in PTP1B(-/-) mice maintained on mixed genetic background (C57Bl/6J × 129Sv/J). Whereas fat mass and adipocyte size were increased in wild-type control mice at 16 months, these parameters did not change with aging in PTP1B(-/-) mice. Increased levels of pro-inflammatory cytokines, crown-like structures, and hypoxia-inducible factor (HIF)-1α were observed only in adipose tissue from 16-month-old wild-type mice. Similarly, islet hyperplasia and hyperinsulinemia were observed in wild-type mice with aging-associated obesity, but not in PTP1B(-/-) animals. Leanness in 16-month-old PTP1B(-/-) mice was associated with increased energy expenditure. Whole-body insulin sensitivity decreased in 16-month-old control mice; however, studies with the hyperinsulinemic-euglycemic clamp revealed that PTP1B deficiency prevented this obesity-related decreased peripheral insulin sensitivity. At a molecular level, PTP1B expression and enzymatic activity were up-regulated in liver and muscle of 16-month-old wild-type mice as were the activation of stress kinases and the expression of p53. Conversely, insulin receptor-mediated Akt/Foxo1 signaling was attenuated in these aged control mice. Collectively, these data implicate PTP1B in the development of inflammation and insulin resistance associated with obesity during aging and suggest that inhibition of this phosphatase by therapeutic strategies might protect against age-dependent T2DM.

Age-associated decrease of SIRT1 expression in rat hippocampus: prevention by late onset caloric restriction.

We have studied the effect of aging and late onset caloric restriction (CR) on the expression of SIRT1 in hippocampus and cerebral cortex of the rat. Quantitative analysis showed that there is a significant reduction of SIRT1 protein levels in hippocampus with aging. Late onset, moderate CR prevented the deleterious effect of aging on SIRT1 content. Examination of SIRT1 immunoreactivity in coronal sections from hippocampus supported these results, and confirmed that old animals are able to respond to the beneficial effects of CR by regulating SIRT1 protein expression. Differences in the amounts of SIRT1 transcripts among animal groups were not found, which suggest that post-transcriptional mechanisms could be involved in the effects of aging and CR on SIRT1 expression.

Age-associated development of inflammation in Wistar rats: Effects of caloric restriction.

CONTEXT: Insulin resistance and type 2 Diabetes have been associated to a low grade of inflammation and their prevalence increase with ageing. OBJECTIVE: To analyse the development of inflammation in adipose tissue, liver, muscle and hypothalamus during ageing and the effects of caloric restriction. MATERIALS AND METHODS: We have analysed the expression of inflammatory cytokines (TNFα, IL1-ß, IL-12B and IL-6), proteins involved in macrophage recruitment (MCP-1, CCR2), TLR4 and macrophage markers (CD11c, CD11b and arginase1). Immunohistochemistry of macrophages has also been performed. RESULTS: All studied tissues present signs of inflammation during ageing, but with different pattern and intensity. Caloric restriction decreases the expression of most of inflammatory markers. DISCUSSION AND CONCLUSIONS: These data indicate a role of adiposity in the development of inflammation and insulin resistance during ageing. Dietetic intervention could be a useful tool to ameliorate the development of inflammation and insulin resistance associated with ageing.

Development of insulin resistance during aging: involvement of central processes and role of adipokines.

Aging in mammals associates with the development of peripheral insulin resistance. Additionally, adiposity usually increases with aging and this could play a relevant role in the gradual impairment of insulin action. In fact, fat accretion leads to changes in the expression and circulating concentrations of factors originated in adipose tissue like leptin, resistin and inflammatory cytokines which have been shown to modulate insulin signaling in insulin target tissues acting both, directly or through the central nervous system. Even insulin action on peripheral target tissues has been recently demonstrated to be partially mediated by its central action, suggesting that a decrease in central insulin action could be involved in the development of peripheral insulin resistance. In the present review we analyze the available research data on aging-associated insulin resistance making emphasis in the following aspects: 1) The time-course of development of overall insulin resistance and the evolution of changes in circulating adipokines; 2) The effect of caloric restriction and the decrease of adiposity in insulin action; 3) The influence of changes in the central action of factors like leptin or insulin in the development and maintenance of insulin resistance during aging.