Potential relationship between cytomegalovirus and immunosenescence: Evidence from observational studies

Immunosenescence (IS) occurs as a natural outcome of ageing and may be described as a decline in immune system flexibility and adaptability to sufficiently respond to new, foreign antigens. Potential factors that may precipitate IS include persistent herpesvirus infections, such as cytomegalovirus (CMV). Here, we conducted a review of the literature evaluating the potential association between CMV and IS. Twenty-seven epidemiologic studies that included direct comparisons between CMV-seropositive and CMV-seronegative immunocompetent individuals were analysed. The majority of these studies (n = 20) were conducted in European populations. The strength of evidence supporting a relationship between CMV, and various IS-associated immunologic endpoints was assessed. T-cell population restructuring was the most prominently studied endpoint, described in 21 studies, most of which reported a relationship between CMV and reduced CD4:CD8 T-cell ratio or modified CD8+ T-cell levels. Telomere length (n = 4) and inflammageing (n = 3) were less frequently described in the primary literature, and the association of these endpoints with CMV and IS was less pronounced. An emergent trend from our review is the potential effect modification of the CMV-IS relationship with both sex and age, indicating the importance of considering various effector variables when evaluating associations between CMV and IS. Our analysis revealed plausible mechanisms that may underlie the larger epidemiologic trends seen in the literature that support the indirect effect of CMV on IS. Future studies are needed to clarify CMV-associated and IS-associated immunologic endpoints, as well as in more diverse global and immunocompromised populations.

Impact of COVID-19 on Physical Activity, Fatigue, and Frailty in Community-Dwelling Older Adults: A Cross-Sectional Study

This study aimed to describe the level of physical activity and its relation to fatigue and frailty during the COVID-19 pandemic in community-dwelling older adults aged 80 years and over. Three hundred and ninety-one older adults (aged 86.5 ± 3.00) completed a survey including physical activity, the Mobility Tiredness scale, and the FRAIL scale. Linear regression analysis was conducted to assess whether the variables age, sex, and physical activity (independent factors) were significantly related to fatigue and frailty. Respectively, 30.5% and 24.7% of the participants reported a decrease in walking and in energy-intensive activities; 25.4% reported increased sedentary behavior. A lower level of physical activity was associated with higher levels of fatigue and increased frailty risk (p < .05), independently from psychological symptoms. These results are important because participants with lower levels of physical activity and more sedentary behavior are more likely to feel fatigued and have higher risk to be frail.

Validity and reliability of Eforto®, a system to (self-)monitor grip strength and muscle fatigability in older persons

INTRODUCTION

We developed Eforto®, an innovative system for (self-)monitoring of grip strength (GS) and muscle fatigability (Fatigue Resistance (FR = time until GS decreased to 50% of maximum during sustained contraction) and grip work (GW = area under the strength-time curve)). The Eforto® system consists of a rubber bulb that is wirelessly connected to a smartphone-based application, and a telemonitoring platform. The aim was to evaluate the validity and reliability of Eforto® to measure muscle fatigability.

METHODS

Community-dwelling older persons (n = 61), geriatric inpatients (n = 26) and hip fracture patients (n = 25) were evaluated for GS and muscle fatigability. In community dwellers fatigability was tested twice in the clinic (once with Eforto®, once with Martin Vigorimeter (MV), standard analog handgrip system) and for six consecutive days as a self-assessment at home with Eforto®. In hospitalized participants, fatigability was tested twice using Eforto®, once by a researcher and once by a health professional.

RESULTS

Criterion validity was supported by good to excellent correlations between Eforto® and MV for GS (r = 0.95) and muscle fatigability (FR r = 0.81 and GW r = 0.73), and no significant differences in measurements between both systems. Inter-rater and intra-rater reliability for GW were moderate to excellent (intra-class correlation: 0.59-0.94). The standard error of measurement for GW was small for geriatric inpatients and hip fracture patients (224.5 and 386.5 kPa*s) and higher for community-dwellers (661.5 kPa*s).

DISCUSSION/CONCLUSION

We established the criterion validity and reliability of Eforto® in older community-dwelling persons and hospitalized patients, supporting the implementation of Eforto® for (self-)monitoring of muscle fatigability.

The impact of covid-19 lockdown on the Quality of life, meaningful activities, and frailty in community-dwelling octogenarians: A study in Belgium

OBJECTIVES

To investigate the impact of COVID-19 lockdown on quality of life (QoL), meaningful daily activities, and (pre)frailty in community-dwelling octogenarians.

METHODS

Cross-sectional design with bivariate and multiple linear regression modeling using a stepwise approach examining the level of QoL during the COVID-19 lockdown in a group of 215 community-dwelling octogenarians (M_age = 86.49 ± 3.02). A comprehensive set of biopsychosocial variables (FRAIL scale, general health, engagement in meaningful activities survey, questions on loneliness, and feelings) were used as explaining variables.

RESULTS

Particularly, a decrease in daily activities, social activities, and an increase in free times activities were observed, but the decrease in QoL could be explained by the meaningfulness in activities, together with experiencing emptiness in life, taking ≥ 4 medications a day and feeling down or depressed.

CONCLUSIONS

We tried to understand which components contribute to and might affect a person's QoL caused by restrictions imposed by the governance and its influence on the lives of the community-dwelling octogenarians. As such, this output could be a baseline for the development of minimally impacting countermeasures during future lockdowns.

CLINICAL IMPLICATIONS

Studying lifestyle changes and thus also variables related to QoL during a pandemic, may support policymakers and practitioners to develop relevant interventions.

Does psychological resilience mediate the relation between daily functioning and prefrailty status?

OBJECTIVES

Understanding of prefrailty's relationship with limitations in activities of daily living (ADLs) moderated by psychological resilience is needed, as resilience might support ADLs' maintenance and thus protect against frailty. Therefore, this study aims to analyze the influence of psychological resilience (using the Connor-Davidson Resilience Scale; CD-RISC) on the relation between ADLs and frailty status of older individuals (i.e. prefrail versus robust).

DESIGN

Cross-sectional design.

SETTING

UZ Brussels, Belgium.

PARTICIPANTS

Robust (Fried 0/4;n = 214; Age = 82.3 ± 2.1yrs) and prefrail (Fried 1-2/4; n = 191; Age = 83.8 ±3.2yrs) community-dwelling older individuals were included.

MEASUREMENTS

Frailty scores were obtained from weight loss, exhaustion, gait speed, and grip strength. A total Disability Index (DI) expressed dependency for basic (b-), instrumental (i-), and advanced (a-)ADLs. Mediation was investigated by estimating direct and indirect effects of all levels of ADLs and CD-RISC total score on prefrailty/robustness using a stepwise multiple regression approach.

RESULTS

Prefrailty/robustness significantly correlated with a-ADL-DI (point-biserial correlation (rpb) = 0.098; p<0.05). Adjusted for age and gender, the a-ADL-DI (p<0.05) had a significant protective direct effect against prefrailty. No effects were found with the CD-RISC total score.

CONCLUSIONS

Less limitation in a-ADLs is a directly correlated factor of prefrailty and might represent a higher likelihood of robustness.

Plasma Levels of Interleukin-6 and the Cluster of Differentiation 4/Cluster of Differentiation 8 Ratio in Frailty among Community-dwelling Older People

Background: Frailty has become a major health problem among Indonesian elders. Immunosenescence specifically inflammaging are essential components in the development of frailty. Early screening and timely tailored intervention may effectively prevent or delay the adverse outcomes in elders. This study measured the CD4/CD8 ratio from the immunosenescence pathway and plasma IL-6 levels as inflammatory markers from the inflammaging pathway and observed the correlations between robust and frail elders groups Methods: We conducted a cross-sectional survey. Using multistage random sampling, we enrolled 64 participants across Malang city, divided into frail and robust groups. We analyzed the plasma IL-6 levels and CD4/CD8 ratio using an independent t-test and the Mann–Whitney U test. Results: Significant differences between frail and robust elders were found in age and education level, with the frail participants being older than the robust (p=0.001) and lower educational level (p<0.001). However, plasma IL-6 levels (p=0.936) and the CD4/CD8 ratio (p=0.468) were not statistically different between the groups. Conclusion: Plasma level of IL-6 was found to increase similarly in both groups, while CD4/CD8 ratio was normal and not statistically different between the robust and frail group in elders.

The interrelationship between grip work, self-perceived fatigue and pre-frailty in community-dwelling octogenarians

INTRODUCTION

Low grip work and high feelings of self-perceived fatigue could be an early characteristic of decline in reserve capacity, which comes to full expression as physical frailty in a later stage. When grip work and self-perceived fatigue can be identified as characteristics differentiating between robustness and pre-frailty it might allow to identify pre-frailty earlier. Therefore, this study aimed to investigate whether the combination of grip work and self-perceived fatigue is related to pre-frailty in well-functioning older adults aged 80 and over.

METHODS

Four-hundred and five community-dwelling older adults aged 80 and over (214 robust and 191 pre-frail) were assessed for muscle endurance (grip Work corrected for body weight (GW_bw)), self-perceived fatigue (MFI-20) and frailty state (Fried Frailty Index, FFI). A Capacity to Perceived Vitality ratio (CPV) was calculated by dividing GW_bw by the MFI-20 scores. ANCOVA analysis (corrected for age and gender) was used to compare robust and pre-frail older adults, and binary logistic regressions were applied to analyze the relationship between CPV and pre-frailty status.

RESULTS

Pre-frail older adults who scored negative on the exhaustion item of the FFI still showed significantly lower GW (p < 0.001), CPV ratios (p < 0.001) and higher self-perceived fatigue (p < 0.05) compared to the robust ones. The likelihood for pre-frailty related significantly to higher age, being men and lower CPV ratios. In women, every unit increase in CPV ratio decreased the likelihood for pre-frailty by 78% (OR 0.22; 95% CI: 0.11-0.44), for men this effect was less strong (34%, OR 0.66; 95% CI: 0.47-0.93).

CONCLUSIONS

Pre-frail community-dwelling persons aged 80 years and over without clinical signs of exhaustion on the FFI still experience significantly higher fatigue levels (lower Grip Work, higher self-perceived fatigue and lower CPV levels) compared to robust ones. CPV ratio could therefore be a good tool to identify subclinical fatigue in the context of physical (pre-)frailty.

CMV infection, CD19+ B cell depletion, and Lymphopenia as predictors for unexpected admission in the institutionalized elderly

Background

Chronic infections played a detrimental role on health outcomes in the aged population, and had complex associations with lymphocyte subsets distribution. Our study aimed to explore the predictive roles of chronic infections, lymphopenia, and lymphocyte subsets on unexpected admission and mortality in the institutionalized oldest-old during 3 year follow-up period.

Results

There were 163 participants enrolled prospectively with median age of 87.3 years (IQR: 83.1–90.2), male of 88.3%, and being followed for 156.4 weeks (IQR: 136.9–156.4 weeks). The unexpected admission and mortality rates were 55.2 and 24.5% respectively. The Cox proportional hazards models demonstrated the 3rd quartile of cytomegalovirus IgG (OR: 3.26, 95% CI: 1.55–6.84), lymphopenia (OR: 2.85, 95% CI: 1.2–6.74), and 1st quartile of CD19⁺ B cell count (OR: 2.84, 95% CI: 1.29–6.25) predicted elevated risks of unexpected admission after adjusting for potential confounders; while the 3rd quartile of CD3⁺ T cell indicated a reduced risk of mortality (OR: 0.19, 95% CI: 0.05–0.71). Negative association between CMV IgG and CD19⁺ B cell count suggested that CMV infection might lead to B cell depletion via decreasing memory B cells repertoire.

Conclusions

CMV infection, lymphopenia, and CD19⁺ B cell depletion might predict greater risk of unexpected admission, while more CD3⁺ T cell would suggest a reduced risk of mortality among the oldest-old population. A non-linear or U-shaped relationship was supposed between health outcomes and CMV infection, CD3⁺ T cell, or CD19⁺ B cell counts. Further prospective studies with more participants included would be needed to elucidate above findings.

Fatigue and the prediction of negative health outcomes: A systematic review with meta-analysis

INTRODUCTION

Fatigue is a common complaint among older adults. Evidence grows that fatigue is linked to several negative health outcomes. A general overview of fatigue and its relationship with negative health outcomes still lacks in the existing literature. This brings complications for healthcare professionals and researchers to identify fatigue-related health risks. Therefore, this study gives an overview of the prospective predictive value of the main negative health outcomes for fatigue in community-dwelling older adults.

METHODS

PubMed, Web of Knowledge and PsycINFO were systematically screened for prospective studies regarding the relationship between fatigue and negative health outcomes resulting in 4595 articles (last search 5th March 2020). Meta-analyses were conducted in RevMan using Odds ratios (ORs), Hazard ratios (HRs) and relative risk ratios (RR) that were extracted from the included studies. Subgroup-analyses were performed based on (1) gender (male/female), (2) length of follow-up and (3) fatigue level (low, medium and high).

RESULTS

In total, thirty articles were included for this systematic review and meta-analysis encompassing 152 711 participants (age range 40-98 years), providing information on the relationship between fatigue and health outcomes. The results showed that fatigue is related to an increased risk for the occurrence of all studied health outcomes (range OR 1.299-3.094; HR/RR 1.038-1.471); for example, mortality OR 2.14 [1.74-2.63]; HR/RR 1.44 [1.28-1.62]), the development of disabilities in basic activities of daily living (OR 3.22 [2.05-5.38]), or the occurrence of physical decline (OR 1.42 [1.29-1.57]).

CONCLUSION

Overall fatigue increases the risk for developing negative health outcomes. The analyses presented in this study show that fatigue related physical decline occurs earlier than hospitalization, diseases and mortality, suggesting the importance of early interventions.

Prefrailty: The Relationship Between Daily Activities and Social Participation in Older Persons

OBJECTIVES

To analyze prefrailty's relationship with limitations in activities of daily living (ADLs) and restrictions in social participation.

METHOD

Robust (Fried 0/4; n = 214; M_age = 82.3 years [SD ±2.1]) and prefrail (Fried 1-2/4; n = 191; M_age = 83.8 years [SD ±3.2]) community-dwelling older individuals were included. Frailty scores were obtained from weight loss, exhaustion, gait speed, and grip strength. A total disability index (DI) expressed dependency for basic (b-), instrumental (i-), and advanced (a-)ADLs. Total participation score, being a member, total number of memberships, being a board member, level of participation, membership over time, volunteering, and formal participation represented social participation.

RESULTS

Logistic regression retained age (OR = 1.224; 95% CI = [1.122, 1.335]), sex (OR = 3.818; 95% CI = [2.437, 5.982]), and a-ADL-DI (OR = 1.230; 95% CI = [1.018, 1.486]) as variables significantly related to prefrailty (68.3%; χ² = 68.25; df = 3; p < .001).

DISCUSSION

Subtle limitations in a-ADLs, higher age, and being a man were associated with prefrailty, revealing the possible role of personal and culturally related a-ADLs as red flags for (pre)frailty.

Effect of Antihypertensive and Statin Medication Use on Muscle Performance in Community-Dwelling Older Adults Performing Strength Training

OBJECTIVES

Antihypertensive drugs (AHTD) and statins have been shown to have effects beyond their primarily designed purpose; here we investigate their possible effect on muscle performance and strength in older adults following a physical exercise programme.

DESIGN

The Senior PRoject INtensive Training (SPRINT) study is a randomised, controlled clinical trial designed to evaluate the effects of physical exercise on the immune system and muscle performance in older adults.

PARTICIPANTS

In this secondary analysis, we included 179 independent participants (aged 65 years and above). We applied further categorisation based on medication use: AHTD (including, angiotensin-converting enzyme inhibitors [ACEI], angiotensin II receptor blockers [ARB], β-blockers, and other AHTD) and statins.

INTERVENTION

Participants were allocated randomly to one of the three exercise protocols: intensive strength training 3 times/week (3 × 10 repetitions at 80% of one-repetition maximum), strength endurance training (2 × 30 repetitions at 40% of one-repetition maximum), or control (passive stretching exercise) for 6 weeks.

MEASUREMENTS

The change in maximal hand grip strength (GS), muscle fatigue resistance (FR), Muscle Strength Index (MSI), the 6-min walk test (6MWT), and Timed Up and Go Test (TUG) were assessed before and after 6 weeks of training.

RESULTS

After 6 weeks, muscle strength (MSI and TUG) improved significantly in all training groups compared to baseline, independently of AHTD use. Moreover, AHTD had no effect on exercise improvements, with no significant differences between medication groups, except for TUG in ARB users, which exhibited a significantly lower performance. On the other hand, statin users presented a significantly longer FR time, indicating better performance compared to non-users. Finally, medication did not affect the participants' commitment to the training programme.

CONCLUSION

Our study showed that statins and ARB usage might affect participant's response to strength training. Nevertheless, 6 weeks of training significantly improved muscle strength and performance irrespective of AHTD or statin use.

Horticultural Therapy Reduces Biomarkers of Immunosenescence and Inflammaging in Community-Dwelling Older Adults: A Feasibility Pilot Randomized Controlled Trial

BACKGROUND

With the challenges that aging populations pose to health care, interventions that facilitate alleviation of age-related morbidities are imperative. A prominent risk factor for developing age-related morbidities is immunosenescence, characterized by increased chronic low-grade inflammation, resulting in T-cell exhaustion and senescence. Contact with nature and associated physical activities have been shown to boost immunity in older adults and may be promoted in the form of horticultural therapy (HT). We aimed to examine the effects of HT on immunosenescence.

METHOD

We conducted a randomized controlled trial with 59 older adults assigned to either the HT intervention or waitlist control group. Older adults in the HT intervention group underwent HT intervention program over 6 months. Venous blood was drawn at baseline and at the third and sixth month from the commencement of this study. For participants who attended all 3 blood collection time points (HT: n = 22; waitlist: n = 24), flow cytometry analysis was performed on whole blood samples to evaluate the kinetics of lymphocyte subsets over the intervention period, revealing the composition of CD4+ and CD8+ subsets expressing exhaustion markers-CD57, CTLA4, and KLRG1. Enzyme-linked immunosorbent assays were employed to measure changes in plasma IL-6 levels.

RESULTS

HT is associated with increased numbers of naive CD8+ T cells and fewer CTLA4-expressing terminally differentiated effector CD4+ and CD8+ memory T cells re-expressing CD45RA (TEMRA). Furthermore, IL-6 levels were reduced during HT, and the frequencies of naive and TEMRA CD8+ T cells were found to be associated with IL-6 levels.

CONCLUSION

HT is associated with a reduction in the levels of biomarkers that measure the extent of T-cell exhaustion and inflammaging in older adults. The positive effects of HT on T-cell exhaustion were associated with the reduction of IL-6 levels.

Strength Endurance Training but Not Intensive Strength Training Reduces Senescence-Prone T Cells in Peripheral Blood in Community-Dwelling Elderly Women

Aging is characterized by a progressive decline in immune function known as immunosenescence. Although the causes of immunosenescence are likely to be multifactorial, an age-associated accumulation of senescent T cells and decreased naive T-cell repertoire are key contributors to the phenomenon. On the other hand, there is a growing consensus that physical exercise may improve immune response in aging. However, the optimum training modality required to obtain beneficial adaptations in older subjects is lacking. Therefore, we aimed to investigate the effects of exercise modality on T-cell phenotypes in older women. A total of 100 women (aged ≥ 65 years) were randomized to either intensive strength training (80% of one-repetition maximum ), strength endurance training (40% one-repetition maximum), or control (stretching exercise) for 2-3 times per week during 6 weeks. The T-cell percentages and absolute counts were determined using flow cytometry and a hematology analyzer. C-reactive protein was measured using immunonephelometry. We report for the first time that 6 weeks of strength endurance training significantly decreased the basal percentage and absolute counts of senescence-prone T cells, which was positively related to the number of training sessions performed. Conceivably, training protocols with many repetitions-at a sufficiently high external resistance-might assist the reduction of senescence-prone T cells in older women.

Six weeks of strength endurance training decreases circulating senescence-prone T-lymphocytes in cytomegalovirus seropositive but not seronegative older women

Background

Ageing is associated with a decline in immune function termed immunosenescence. This process is characterized amongst others by less naive T-cells and more senescent phenotypes, which have been implicated in the pathogenesis of many age-related diseases. Thus far, reports regarding the long-term adaptation effects of exercise on T-cell phenotypes are scant and largely equivocal. These inconsistencies may be due to potential contributors to immunosenescence, particularly cytomegalovirus infection, which is considered a hallmark of T-cell senescence. Therefore, we sought to investigate the impact of cytomegalovirus serostatus on the distribution of peripheral T-cell subsets following long-term exercise in older women.

Methods

One hundred women (aged 65 years and above) were randomized to 3 times/weekly training at either intensive strength training (3 × 10 repetitions at 80% of one-repetition maximum, n = 31), strength endurance training (2 × 30 repetitions at 40% of one-repetition maximum, n = 33), or control (passive stretching exercise, n = 36) for 6 weeks. All training sessions were supervised by trained instructors to minimize the risk of injury and to ensure that the participants adhered to the training protocol throughout the entire range of motion. The T-cell percentages and absolute blood counts were determined before and after 6 weeks (24 h–48 h after the last training session) using flow cytometry and a haematology analyser. Cytomegalovirus antibodies were measured in serum using Architect iSystem and cytomegalovirus serostatus was balanced in the three intervention groups. C-reactive protein was measured using immunonephelometry.

Results

We report for the first time that 6 weeks of strength endurance training significantly decreased senescence-prone T-cells along with a small increase in the number of CD8– naive T-cells in blood. The absolute counts of senescent-like T-cells decreased by 44% (from 26.03 ± 35.27 to 14.66 ± 21.36 cells/μL, p < 0.01) and by 51% (from 6.55 ± 12.37 to 3.18 ± 6.83 cells/μL, p < 0.05) for the CD8+ and CD8– T-cell pools, respectively. Intriguingly, these changes were observed in cytomegalovirus seropositive, but not cytomegalovirus seronegative individuals.

Conclusions

In conclusion, the present study shows that strength endurance training leads to a reduction in circulating senescence-prone T-cells in cytomegalovirus seropositive older women. It remains to be established if monitoring of peripheral senescence-prone T-cells may have utility as cellular biomarkers of immunosenescence.

Electronic supplementary material

The online version of this article (10.1186/s12979-019-0157-8) contains supplementary material, which is available to authorized users.

Thirteen weeks of supplementation of vitamin D and leucine-enriched whey protein nutritional supplement attenuates chronic low-grade inflammation in sarcopenic older adults: the PROVIDE study

Background

A chronic low-grade inflammatory profile (CLIP) is associated with sarcopenia in older adults. Protein and Vitamin (Vit)D have immune-modulatory potential, but evidence for effects of nutritional supplementation on CLIP is limited.

Aim

To investigate whether 13 weeks of nutritional supplementation of VitD and leucine-enriched whey protein affected CLIP in subjects enrolled in the PROVIDE-study, as a secondary analysis.

Methods

Sarcopenic adults (low skeletal muscle mass) aged ≥ 65 years with mobility limitations (Short Physical Performance Battery 4–9) and a body mass index of 20–30 kg/m² were randomly allocated to two daily servings of active (n = 137, including 20 g of whey protein, 3 g of leucine and 800 IU VitD) or isocaloric control product (n = 151) for a double-blind period of 13 weeks. At baseline and after 13 weeks, circulating interleukin (IL)-8, IL-1 receptor antagonist (RA), soluble tumor-necrosis-factor receptor (sTNFR)1, IL-6, high-sensitivity C-reactive protein, pre-albumin and 25-hydroxyvitamin(OH)D were measured. Data-analysis included repeated measures analysis of covariance (corrected for dietary VitD intake) and linear regression.

Results

IL-6 and IL-1Ra serum levels showed overall increases after 13 weeks (p = 0.006 and p < 0.001, respectively). For IL-6 a significant time × treatment interaction (p = 0.046) was observed, with no significant change over time in the active group (p = 0.155) compared to control (significant increase p = 0.012). IL-8 showed an overall significant decrease (p = 0.03). The change in pre-albumin was a significant predictor for changes in IL-6 after 13 weeks.

Conclusions

We conclude that 13 weeks of nutritional supplementation with VitD and leucine-enriched whey protein may attenuate the progression of CLIP in older sarcopenic persons with mobility limitations.

Electronic supplementary material

The online version of this article (10.1007/s40520-019-01208-4) contains supplementary material, which is available to authorized users.

Immune aging in diabetes and its implications in wound healing

Immune systems have evolved to recognize and eliminate pathogens and damaged cells. In humans, it is estimated to recognize 109 epitopes and natural selection ensures that clonally expanded cells replace unstimulated cells and overall immune cell numbers remain stationary. But, with age, it faces continuous repertoire restriction and concomitant accumulation of primed cells. Changes shaping the aging immune system have bitter consequences because, as inflammatory responses gain intensity and duration, tissue-damaging immunity and inflammatory disease arise. During inflammation, the glycolytic flux cannot cope with increasing ATP demands, limiting the immune response's extent. In diabetes, higher glucose availability stretches the glycolytic limit, dysregulating proteostasis and increasing T-cell expansion. Long-term hyperglycemia exerts an accumulating effect, leading to higher inflammatory cytokine levels and increased cytotoxic mediator secretion upon infection, a phenomenon known as diabetic chronic inflammation. Here we review the etiology of diabetic chronic inflammation and its consequences on wound healing.

Early Senescence and Leukocyte Telomere Shortening in SCHIZOPHRENIA: A Role for Cytomegalovirus Infection?

Schizophrenia is a severe, chronic mental disorder characterized by delusions and hallucinations. Several evidences support the link of schizophrenia with accelerated telomeres shortening and accelerated aging. Thus, schizophrenia patients show higher mortality compared to age-matched healthy donors. The etiology of schizophrenia is multifactorial, involving genetic and environmental factors. Telomere erosion has been shown to be accelerated by different factors including environmental factors such as cigarette smoking and chronic alcohol consumption or by psychosocial stress such as childhood maltreatment. In humans, telomere studies have mainly relied on measurements of leukocyte telomere length and it is generally accepted that individuals with short leukocyte telomere length are considered biologically older than those with longer ones. A dysregulation of both innate and adaptive immune systems has been described in schizophrenia patients and other mental diseases supporting the contribution of the immune system to disease symptoms. Thus, it has been suggested that abnormal immune activation with high pro-inflammatory cytokine production in response to still undefined environmental agents such as herpesviruses infections can be involved in the pathogenesis and pathophysiology of schizophrenia. It has been proposed that chronic inflammation and oxidative stress are involved in the course of schizophrenia illness, early onset of cardiovascular disease, accelerated aging, and premature mortality in schizophrenia. Prenatal or neonatal exposures to neurotropic pathogens such as Cytomegalovirus or Toxoplasma gondii have been proposed as environmental risk factors for schizophrenia in individuals with a risk genetic background. Thus, pro-inflammatory cytokines and microglia activation, together with genetic vulnerability, are considered etiological factors for schizophrenia, and support that inflammation status is involved in the course of illness in schizophrenia.