Ciliary neurotrophic factor in the hypothalamus of obese mice

Ciliary neurotrophic factor (CNTF) is a potent survival molecule for a large number of neuronal and glial cells. We previously found that in mouse hypothalamus CNTF is expressed by ependymal cells and tanycyctes lining the third ventricle and in a few scattered glial cells (Severi et al., 2012). Exogenously administered CNTF produces an anorectic effect via activation of hypothalamic neurons, and also stimulates neurogenesis in mouse hypothalamus. Thus, we evaluated CNTF expression in the hypothalamus of mice feeding a high fat diet (HFD, 50% of calories as fat) and in mice kept in a calorie restriction (CR) regimen (60% of individual mean food intake). RT-PCR showed a significant increase of both CNTF and CNTF receptor α (CNTFRα) mRNAs in the hypothalamus of the HFD mice; conversely, CR mice exhibited a significant decrease of CNTF and CNTFRα. Immunohistochemistry showed that in the HFD mice the hypothalamic increase of CNTF was restricted to the tanycytes located in the ependymal layer bordering the median eminence and sending their processes to the arcuate, ventromedial and dorsomedial nuclei, the tuberal part of the hypothalamus strongly involved in energy balance regulation. Stimulation of cells bearing the CNTFRα induces specific activation of the signal transducer and activator of transcription 3 (STAT3) signalling system. Intraperitoneal treatment with recombinant CNTF and detection of the nuclear expression of phospho-STAT3 (P-STAT3) confirmed an increased responsiveness of HFD mice hypothalamus to CNTF and, conversely, a decreased expression of the receptor in the mice kept in the CR regimen. Interestingly, only in the HFD mice CNTF was able to activate a large population of neurons dispersed in the arcuate, ventromedial and dorsomedial nuclei

Millets and Cereal Meals from the Early Iron Age Underwater Settlement of “Gran Carro” (Bolsena Lake, Central Italy)

Archeobotanical materials recovered from pottery vessels originating from the underwater archeological site of “Gran Carro”, located in Central Italy on the shore of Bolsena Lake, were analyzed to obtain new insight into the agricultural habits present in this Iron Age settlement. The archeobotanical study of cereal remains was combined with analytical data obtained from an amorphous organic residue using optical microscopy, SEM-EDS, ATR/FT-IR and Py-GC/MS. The cereal remains of emmer wheat (Triticum dicoccum), barley (Hordeum vulgare), broomcorn millet (Panicum miliaceum), and foxtail millet (Setaria italica) were identified as the preferred crops used for food and/or fodder at the site. The presence of charred millets, which have been directly dated by AMS, confirms consumption at the site and adds to the little-known background of millet use in central Italy. The find of millets in a perilacustrine pile-dwelling during a period when the water level of the Bolsena Lake was several meters lower than at present, attesting to a general dry period, suggests that the cultivation of millets, complementing more productive crops of wheat and barley, may have been favored by the availability of a large seasonally dry coastal plain, characterized by poor and sandy soils unsuitable for more demanding cereals

Muscle and adipose tissue morphology, insulin sensitivity and beta-cell function in diabetic and nondiabetic obese patients: effects of bariatric surgery

Obesity is characterized by insulin-resistance (IR), enhanced lipolysis, and ectopic, inflamed fat. We related the histology of subcutaneous (SAT), visceral fat (VAT), and skeletal muscle to the metabolic abnormalities, and tested their mutual changes after bariatric surgery in type 2 diabetic (T2D) and weight-matched non-diabetic (ND) patients. We measured IR (insulin clamp), lipolysis ((2)H5-glycerol infusion), ß-cell glucose-sensitivity (ß-GS, mathematical modeling), and VAT, SAT, and rectus abdominis histology (light and electron microscopy). Presurgery, SAT and VAT showed signs of fibrosis/necrosis, small mitochondria, free interstitial lipids, thickened capillary basement membrane. Compared to ND, T2D had impaired ß-GS, intracapillary neutrophils and higher intramyocellular fat, adipocyte area in VAT, crown-like structures (CLS) in VAT and SAT with rare structures (cyst-like) ~10-fold larger than CLS. Fat expansion was associated with enhanced lipolysis and IR. VAT histology and intramyocellular fat were related to impaired ß-GS. Postsurgery, IR and lipolysis improved in all, ß-GS improved in T2D. Muscle fat infiltration was reduced, adipocytes were smaller and richer in mitochondria, and CLS density in SAT was reduced. In conclusion, IR improves proportionally to weight loss but remains subnormal, whilst SAT and muscle changes disappear. In T2D postsurgery, some VAT pathology persists and beta-cell dysfunction improves but is not normalized

Cells

Via activation of the cannabinoid type-1 (CB1) receptor, endogenous and exogenous cannabinoids modulate important biochemical and cellular processes in adipocytes. Several pieces of evidence suggest that alterations of mitochondrial physiology might be a possible mechanism underlying cannabinoids’ effects on adipocyte biology. Many reports suggest the presence of CB1 receptor mRNA in both white and brown adipose tissue, but the detailed subcellular localization of CB1 protein in adipose cells has so far been scarcely addressed. In this study, we show the presence of the functional CB1 receptor at different subcellular locations of adipocytes from epididymal white adipose tissue (eWAT) depots. We observed that CB1 is located at different subcellular levels, including the plasma membrane and in close association with mitochondria (mtCB1). Functional analysis in tissue homogenates and isolated mitochondria allowed us to reveal that cannabinoids negatively regulate complex-I-dependent oxygen consumption in eWAT. This effect requires mtCB1 activation and consequent regulation of the intramitochondrial cAMP-PKA pathway. Thus, CB1 receptors are functionally present at the mitochondrial level in eWAT adipocytes, adding another possible mechanism for peripheral regulation of energy metabolism. © 2022 by the authors.Role du recepteur CB1 mitocondriel du tissue adipeux dans la regulation de la balance energetiqueVieillissement et démence: un rôle hormonal?Development of pregnenolone derivatives as allosteric inhibitors of CB1 cannabinoid receptors for thetreatment of schizophrenia and psychotic syndrome

The city of Yakutsk: a case of study for human brown adipose tissue in extremely cold conditions

The discovery of the presence of functional brown adipose tissue (BAT) also in healthy humans [1-3] has focused the attention of the scientific community on the possibility to expand body BAT content as a therapeutic strategy for the treatment and prevention of obesity and the associated metabolic disorders. Indeed, white-to- brown adipocyte transdifferentiation, leading to “browning” of the adipose organ, has been shown to reduce body weight and improve metabolic parameters in obese and insulin-resistant animal models. BAT from subject exposed daily to extremely cold outdoor temperatures has never been studied through morphological techniques. In this context, an exciting case of study are the citizens of Yakutsk, an East- ern Siberian population exposed to the annual average temperature of -10 °C, that peaks up to -50°C during winter. In autoptic fat biopsies from a 54-year-old patient living in Yakutsk BAT is present in the perirenal and para-aortic fat specimens. Importantly, the mean adipocyte area of the subcutaneous fat from this patient is significantly lower than the mean area of subcutaneous adipocytes obtained from age- and sex-matched Italian patients. Statistical analysis of data obtained from the Territorial Organ of the Federal State Statistics Service of the Republic of Sakha (Yakutia), the Yakut Republican Medical Information and Analytical Center of the Ministry of Health of Yakutia showed a correlation between home heating and type-2 diabetes incidence during the years from 1994 to 2013, a period in which the indoor temperature increased significantly. The nutritional values of food consumed during these years also changed in parallel with the worsening of inhabitants metabolic health conditions. Taken together these data suggest a possible link between the metabolic condi- tions of inhabitants of Yakutia and the living temperature experienced

Treatment with r-irisin prevents and recovers disuse-induced bone loss and muscle atrophy

Irisin is a hormone-like myokine secreted from skeletal muscle in response to exercise. We previously showed that treatment with recombinant Irisin (r-Irisin) in healthy mice improved cortical bone mass and geometry, supporting the idea that Irisin recapitulates some of the most important benefits of physical exercise on the skeleton and plays protective role on bone health (1). Here we show that treatment with r-Irisin prevented bone loss in hind-limb suspended mice when administered during suspension and induced recovery of bone mass when mice were injected after bone loss due to a suspension period of 4 weeks. MicroCT analysis of femurs showed that r-Irisin preserved both cortical and trabecular bone mineral density, and prevented the dramatic decrease of the trabecular bone volume fraction. Moreover, r-Irisin inhibited muscle mass decline during unloading, keeping proper fiber cross-sectional area. Notably, the decrease in myosin type II expression (MyHC II) in vastus lateralis of unloaded mice treated with r-Irisin was completely prevented. Our data reveal that r-Irisin treatment protects from disuse induced bone loss and muscle atrophy in mice. If these results will translate to humans, they may support a promising clinical strategy for the prevention and treatment of both osteoporosis and sarcopenia, particularly applicable to those patients who cannot perform physical activity, as occurs during aging, immobility and microgravity during space flight missions

Dietary essential amino acids for the treatment of heart failure with reduced ejection fraction

Aims: Heart failure with reduced ejection fraction (HFrEF) is a leading cause of mortality worldwide, requiring novel therapeutic and lifestyle interventions. Metabolic alterations and energy production deficit are hallmarks and thereby promising therapeutic targets for this complex clinical syndrome. We aim to study the molecular mechanisms and effects on cardiac function in rodents with HFrEF of a designer diet in which free essential amino acids - in specifically designed percentages - substituted for protein. Methods and results: Wild-type mice were subjected to transverse aortic constriction (TAC) to induce left ventricle (LV) pressure overload or sham surgery. Whole body glucose homeostasis was studied with glucose tolerance test, while myocardial dysfunction and fibrosis were measured with echocardiogram and histological analysis. Mitochondrial bioenergetics and morphology were investigated with oxygen consumption rate measurement and electron microscopy evaluation. Circulating and cardiac non-targeted metabolite profiles were analyzed by ultrahigh performance liquid chromatography-tandem mass spectroscopy, while RNA sequencing was used to identify signalling pathways mainly affected. The amino acid-substituted diet shows remarkable preventive and therapeutic effects. This dietary approach corrects the whole-body glucose metabolism and restores the unbalanced metabolic substrate usage - by improving mitochondrial fuel oxidation - in the failing heart. In particular, biochemical, molecular, and genetic approaches suggest that renormalization of branched-chain amino acid oxidation in cardiac tissue, which is suppressed in HFrEF, plays a relevant role. Beyond the changes of systemic metabolism, cell-autonomous processes may explain at least in part the diet's cardioprotective impact. Conclusion: Collectively, these results suggest that manipulation of dietary amino acids, and especially essential amino acids, is a potential adjuvant therapeutic strategy to treat systolic dysfunction and HFrEF in humans

Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P < .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients

Ciliary neurotrophic factor in the mouse hypothalamus. A possible role in energy balance homeostasis

Il fattore neurotrofico ciliare (ciliary neurotrophic factor, CNTF) è un fattore neurotrofico attivo sia su neuroni che su cellule gliali. Poiché in epoca postnatale il CNTF mantiene il trofismo dei circuiti motori, eventuali effetti terapeutici di Axokine, analogo ricombinante del CNTF umano, sono stati valutati su pazienti affetti da patologie motorie. Mentre gli effetti sulle abilità motorie si sono rivelati scarsi, i pazienti trattati con Axokine hanno presentato un significativo calo ponderale legato ad una riduzione dell’appetito. Numerosi gruppi di ricerca hanno quindi valutato l’azione del CNTF nell’ipotalamo, sede dei circuiti neuronali che nei mammiferi regolano il bilancio energetico. Nel complesso, il CNTF esogeno determina sazietà, riduzione dell’introito di cibo e aumento della spesa energetica, modulando funzione e struttura dei circuiti neuronali ipotalamici sensibili alla leptina, insulina ed altri fattori circolanti. Nulla è noto circa la presenza e la distribuzione del CNTF nell’ipotalamo, in condizioni normali o patologiche, e in questo studio condotto su topi, ci siamo proposti di valutare 1) se il CNTF è espresso nell’ipotalamo, 2) quali tipi cellulari lo producono e 3) se l’espressione ipotalamica del CNTF è modulata da differenti condizioni nutritive. I dati di RT-PCR e Western blotting mostrano che il CNTF è costitutivamente espresso nell’ipotalamo di topi tenuti in condizioni standard. L’analisi immunoistochimica mostra che il CNTF è prodotto da alcune cellule gliali in sede subependimale e dall’ependima del terzo ventricolo, dove sono intensamente positivi i taniciti dell’ipotalamo tuberale e mammillare, regioni ipotalamiche che contengono le popolazioni neuronali che regolano il comportamento alimentare. Al fine di verificare un possibile ruolo del CNTF endogeno nella regolazione del bilancio energetico, l’espressione del CNTF è stata studiata in topi resi obesi da dieta ad alto contenuto lipidico e, all’opposto, in topi magri, tenuti in condizione di restrizione calorica (60% del normale introito calorico giornaliero). I risultati hanno evidenziato che l’obesità da dieta iperlipidica determina un significativo incremento dell’espressione di CNTF nei taniciti delle regioni tuberale e mammillare dell’ipotalamo, mentre la restrizione calorica ha un effetto opposto. Per confermare il coinvolgimento del CNTF nella regolazione del bilancio energetico a livello ipotalamico, abbiamo quindi studiato l’espressione del recettore specifico. I dati di RT-PCR e Western blotting hanno mostrato che, parallelamente a quanto osservato per il ligando, l’obesità da dieta iperlipidica determina un aumento significativo dell’espressione ipotalamica del recettore per il CNTF, mentre la restrizione calorica si associa ad una sua significativa riduzione. Non essendo disponibili anticorpi specifici per il recettore del CNTF, i target cellulari del CNTF sono stati individuati mediante valutazione immunoistochimica dell’attivazione della specifica via di trasduzione (Jak1/2-STAT3 pathway) in topi trattati in acuto con bolo di CNTF. Le principali cellule target del CNTF sono le cellule ependimali, tra cui i taniciti. A conferma dei dati di biologia molecolare, nei topi obesi la responsività di queste cellule al CNTF aumenta, all’opposto nei topi tenuti in condizioni di restrizione calorica si riduce. In conclusione, il CNTF è prodotto dall’ependima del terzo ventricolo, ed in particolare dai taniciti della regione tuberale e mammillare. Esso rappresenta un nuovo fattore di sazietà coinvolto nella regolazione fisiopatologica dei circuiti ipotalamici del bilancio energetico. La modulazione farmacologica della sua espressione e/o del recettore specifico potrebbe rappresentare in futuro un approccio al trattamento farmacologico dell’obesità umana

Early Life Stress, Brain Development, and Obesity Risk: Is Oxytocin the Missing Link?

Obesity disease results from a dysfunctional modulation of the energy balance whose master regulator is the central nervous system. The neural circuitries involved in such function complete their maturation during early postnatal periods, when the brain is highly plastic and profoundly influenced by the environment. This phenomenon is considered as an evolutionary strategy, whereby metabolic functions are adjusted to environmental cues, such as food availability and maternal care. In this timeframe, adverse stimuli may program the body metabolism to maximize energy storage abilities to cope with hostile conditions. Consistently, the prevalence of obesity is higher among individuals who experienced early life stress (ELS). Oxytocin, a hypothalamic neurohormone, regulates the energy balance and modulates social, emotional, and eating behaviors, exerting both central and peripheral actions. Oxytocin closely cooperates with leptin in regulating energy homeostasis. Both oxytocin and leptin impact the neurodevelopment during critical periods and are affected by ELS and obesity. In this review article, we report evidence from the literature describing the effect of postnatal ELS (specifically, disorganized/inconstant maternal care) on the vulnerability to obesity with a focus on the role of oxytocin. We emphasize the existing research gaps and highlight promising directions worthy of exploration. Based on the available data, alterations in the oxytocin system may in part mediate the ELS-induced susceptibility to obesity