Autophagy regulates the release of exercise factors and their beneficial effects on spatial memory recall

Exercise promotes learning and memory recall as well as rescues cognitive decline associated with aging. The positive effects of exercise are mediated by circulatory factors that predominantly increase Brain Derived Neurotrophic Factor (BDNF) signaling in the hippocampus. Identifying the pathways that regulate the release of the circulatory factors by various tissues during exercise and that mediate hippocampal Mus musculus Bdnf expression will allow us to harness the therapeutic potential of exercise. Here, we report that two weeks of voluntary exercise in male mice activates autophagy in the hippocampus by increasing LC3B protein levels (p = 0.0425) and that autophagy is necessary for exercise-induced spatial learning and memory retention (p < 0.001; exercise + autophagy inhibitor chloroquine CQ versus exercise). We place autophagy downstream of hippocampal BDNF signaling and identify a positive feedback activation between the pathways. We also assess whether the modulation of autophagy outside the nervous system is involved in mediating exercise's effect on learning and memory recall. Indeed, plasma collected from young exercise mice promote spatial learning (p = 0.0446; exercise versus sedentary plasma) and memory retention in aged inactive mice (p = 0.0303; exercise versus sedentary plasma), whereas plasma collected from young exercise mice that received the autophagy inhibitor chloroquine diphosphate failed to do so. We show that the release of exercise factors that reverse the symptoms of aging into the circulation is dependent on the activation of autophagy in young animals. Indeed, we show that the release of the exercise factor, beta-hydroxybutyrate (DBHB), into the circulation, is autophagy-dependent and that DBHB promotes spatial learning and memory formation (p = 0.0005) by inducing hippocampal autophagy (p = 0.0479). These results implicate autophagy in peripheral tissues and in the hippocampus in mediating the effects of exercise on learning and memory recall and identify DBHB as a candidate endogenous exercise factor whose release and positive effects are autophagy-dependent.

Descriptive epidemiology of soft tissue and bone sarcomas in Lebanon

OBJECTIVES

Most epidemiologic studies on soft tissue sarcomas (STS) and bone sarcomas (BS) are performed in western countries, with few in the Middle East and North Africa region. We describe the epidemiology of sarcomas in Lebanon using the medical records database at the American University of Beirut Medical Center (AUBMC).

METHODS

This single-center retrospective cohort study included patients with sarcomas registered in the database between 2015 and 2019. Their charts were reviewed for baseline characteristics, tumor biology and location, treatment modalities, recurrence, metastasis, and death.

RESULTS

The cohort included 234 patients with STS and 99 patients with BS. Most tumors were <10 cm in size. The most common subtypes were liposarcoma for STS and osteosarcoma for BS. The most common location of STS was the thigh. The most frequent sites of STS metastasis were the lungs. Histological subtype, smoking status, and tumor size and grade were significant for progression-free survival (PFS) in patients with STS. By multivariable analysis, smoking was significantly associated with poorer PFS in STS. For BS, only tumor grade was significant for PFS.

CONCLUSION

The epidemiology of sarcomas at AUBMC is similar to that previously reported. Smoking history was associated with poorer survival in patients with STS.

CYR61/CCN1 expression in resected pancreatic ductal adenocarcinoma: A retrospective pilot study of the interaction between the tumors and their surrounding microenvironment

BACKGROUND

CCN1 is an extracellular matrix-associated protein thought to be implicated in tumor-stromal interaction in several solid tumors. The aim of our pilot study was to evaluate the correlation between CCN1 expression in stromal cells, pancreatic intraepithelial neoplasia (PanIN) and pancreatic ductal adenocarcinoma cells in resected pancreatic ductal adenocarcinoma (PDAC) specimens, and correlate that clinically.

METHODS

A total of 42 paraffin-embedded PDAC tumor specimens were stained for CCN1 and evaluated via immunohistochemical (IHC) analysis. Statistical analysis was performed to correlate between CCN1 expression profiles in tumor tissues and clinicopathological parameters of patients.

RESULTS

Our results showed CCN1 (CYR61) gene was highly expressed in PDAC tissues relative to other organ specific tumor tissues. Also, moderate and overexpression of CCN1 in PanIN was associated with PanIN grade 3 tissues. A statistically significant association was found between PanIN CCN1 scores on one hand and cancer stage, cancer grade, and CCN1 expression among ductal tumor cells and adjacent stromal cells on the other hand.

DISCUSSION

The associations demonstrated suggest that CCN1 might be contributing to a substantial role in the interaction between the pancreatic tumors on one hand and their surrounding microenvironment and their precursors on the other hand; hence, it might serve as a potential therapeutic target for PDAC.

Branched-chain amino acids mediate resilience to chronic social defeat stress by activating BDNF/TRKB signaling

How individuals respond to chronic stress varies. Susceptible individuals ultimately develop depression; whereas resilient individuals live normally. In this study, our objective was to examine the effect of branched-chain amino acids (BCAA), commonly used by athletes, on susceptibility to stress. Male C57BL/6 mice were subjected to daily defeat sessions by a CD1 aggressor, for 10 days. On day11, the behavior of mice was assessed using the social interaction test, elevated plus maze and open field. Mice received the BCAA leucine, isoleucine or valine before each defeat session. Furthermore, we examined whether BCAA regulate brain derived neurotrophic factor (BDNF) signaling by using a brain-permeable tropomyosin receptor kinase B (TRKB) inhibitor, ANA-12. We also tested the effect of voluntary exercise and high protein diets on susceptibility to stress. Mice exposed to chronic stress displayed increased susceptibility and social avoidance. BCAA promoted resilience to chronic stress, rescued social avoidance behaviors and increased hippocampal BDNF levels and TRKB activation. Inhibition of TRKB signaling abolished the ability of BCAA to promote resilience to stress and to rescue social avoidance. Interestingly, we found that BCAA activate the exercise-regulated PGC1a/FNDC5 pathway known to induce hippocampal BDNF signaling. Although both voluntary exercise and BCAA promoted resilience to stress, combining them did not yield synergistic effects confirming that they affect similar pathways. We also discovered that high protein diets mimic the effect of BCAA by rescuing social deficits induced by chronic stress and increase Bdnf expression in the hippocampus. Our data indicate that BCAA, exercise and high protein diets rescue susceptibility to stress by activating the hippocampal BDNF/TRKB signaling.

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BCAA promote resilience to stress and rescue social avoidance via activation of hippocampal BDNF/TRKB signaling.

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BCAA induce hippocampal BDNF/TRKB signaling by activating the exercise-regulated PGC1a/FNDC5 pathway.

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BCAA and voluntary exercise affect similar pathways.

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HPD promote resilience to stress, rescue social avoidance and induce hippocampal Bdnf expression.

Lactate is an antidepressant that mediates resilience to stress by modulating the hippocampal levels and activity of histone deacetylases

Chronic stress promotes depression in some individuals, but has no effect in others. Susceptible individuals exhibit social avoidance and anxious behavior and ultimately develop depression, whereas resilient individuals live normally. Exercise counteracts the effects of stress. Our objective was to examine whether lactate, a metabolite produced during exercise and known to reproduce specific brain exercise-related changes, promotes resilience to stress and acts as an antidepressant. To determine whether lactate promotes resilience to stress, male C57BL/6 mice experienced daily defeat by a CD-1 aggressor, for 10 days. On the 11th day, mice were subjected to behavioral tests. Mice received lactate before each defeat session. When compared with control mice, mice exposed to stress displayed increased susceptibility, social avoidance and anxiety. Lactate promoted resilience to stress and rescued social avoidance and anxiety by restoring hippocampal class I histone deacetylase (HDAC) levels and activity, specifically HDAC2/3. To determine whether lactate is an antidepressant, mice only received lactate from days 12-25 and a second set of behavioral tests was conducted on day 26. In this paradigm, we examined whether lactate functions by regulating HDACs using co-treatment with CI-994, a brain-permeable class I HDAC inhibitor. When administered after the establishment of depression, lactate behaved as antidepressant. In this paradigm, lactate regulated HDAC5 and not HDAC2/3 levels. On the contrary, HDAC2/3 inhibition was antidepressant-like. This indicates that lactate mimics exercise's effects and rescues susceptibility to stress by modulating HDAC2/3 activity and suggests that HDAC2/3 play opposite roles before and after establishment of susceptibility to stress.

Identification and characterization of a compound from Cuminum cyminum essential oil with antifibrilation and cytotoxic effect

Amyloid pathology is associated with fibril aggregation of different proteins which results in the progressive damage of affected organs. It is strongly believed that specific small molecules interfere with fibrillation by interacting with the amyloidogenic proteins. We had previously reported the strong and long-term inhibition of fibrillation of hen egg white lysozyme (HEWL) by Cuminum cyminum oil. Herein, it was intended to rationally identify the active anti-amyloidogenic compounds of the oil. After fractionation, the highest inhibitory effect was observed in the toluene-ethyl acetate part of the oil. Gas chromatography-mass spectrometry (GC-MS) analysis of this fraction indicated that eight compounds were predominantly present in the fraction. Unexpectedly, two compounds including terpinolene and limonene, having very similar chemical structures, inhibited and induced fibrillation, respectively. PC12 cells (derived from a transplantable rat pheochromocytoma) were affected by HEWL fibrils, whereas the inhibited forms of fibrils in the presence of terpinolene led to higher levels of viability, as shown by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH) and flow cytometry assays. Molecular local docking analysis suggested a site of interaction for terpinolene in the flexible cleft of the protein. This interaction site is close to tryptophan -62 and -63 and two other hydrophobic residues in the hot spot regions of the protein. Seemingly, these interactions interrupt protein self-assembly and therefore, fibril formation. Despite previously reported small anti-amyloid molecules which have aromatic flat rings, terpinolene ring is not flat. This functionally durable small molecule may aid us toward developing new anti-amyloidogenic compounds with extended activity.

Ratio between positive lymph nodes and total excised axillary lymph nodes as an independent prognostic factor for overall survival in patients with early breast cancer

e22084

Background: The status of the axillary lymph nodes (ALN) in early (stage I and II) breast cancer (BC) patients remains the single most important determinant of overall survival (OS). While the absolute number of positive ALN has been demonstrated to have a significant prognostic impact, new emerging data supports the role of axillary lymph node ratio (ALNR) as an independent prognostic indicator of OS. Methods: We conducted a single-center retrospective review of 1,255 BC patients and analyzed 930 patients with early BC admitted to American University of Beirut Medical Center between 1983 and 2001. Data included age at diagnosis, type of mastectomy, ALN involvement, use of chemotherapy, hormonal therapy, post-operative radiation therapy, tumor size, histological type and grade, lympho-vascular invasion status, hormonal receptor status, and Her-2/neu overexpression and the calculated ALNR (number of positive ALN / total number of excised ALN). Patients were subdivided into 3 groups according to ALNR value (< 0.25, 0.25–0.49, 0.50–1.00). The status of the axillary lymph nodes was analyzed with respect to 5- and 10-year OS. Results: On univariate analysis both the absolute number of positive ALN and the ALNR were significant predictors of OS .The 5- year OS of patients with ALNRs of < 0.25, 0.25–0.49 and 0.50–1.00 was 88%, 72% and 65 % respectively and the 10-year OS was 83%,54% and 51 % respectively . On multivariate analysis only the ALNR remained an independent predictor of overall survival, with a 2.7- and 3.16-fold risk of dying at ALNRs of 0.25 and 0.5, respectively. Conclusions: Our study demonstrated that the ALNR is a stronger factor in predicting OS than the absolute number of positive axillary lymph nodes. ALNR may aid in subdividing patients with positive ALN into low and high risk groups, with potential implications on their subsequent adjuvant management.

No significant financial relationships to disclose.

Recurrent massive haemorrhage from an endoscopically inevident isolated rectal varix

Anorectal varices are identified endoscopically in up to 40% of patients with liver cirrhosis [Misra SP, Dwivedi M, Misra V. Prevalence and factors influencing haemorrhoids, anorectal varices, and colopathy in patients with portal hypertension. Endoscopy 1996;28:340-5] but are an infrequent cause of bleeding and their management remains controversial. We present a patient with chronic hepatitis C virus infection who developed recurrent haemorrhage from an isolated, endoscopically inevident rectal varix in the absence of clinical or endoscopic evidence of portal hypertension. The difficulties in diagnosis and management of anorectal varices are highlighted.

Solid pseudopapillary neoplasm of the pancreas in a 12-year-old female: case report and review of the literature

Solid pseudopapillary neoplasms of the pancreas (SPNP) are rare pancreatic tumors that occur predominantly in young women, with very few cases reported in men. While the origin of the tumor may be unclear, it is characterized by a distinct histological appearance and a clinical course highlighting its low malignant potential. SPNP have an excellent prognosis and are potentially curable provided they are managed appropriately by complete surgical resection. In the rare instances where metastatic disease is encountered, surgical debulking has been shown to prolong survival. The role of chemotherapy and radiation therapy in the management of SPNP is still controversial. We report here on an unusual occurrence of SPNP in the area of the head of the pancreas in a 12-year-old female treated by pancreatico-duodenectomy, together with a review of the literature.

A clinical phase II study of combination Cisplatinum and Vinorelbine followed by Docetaxel as first-line chemotherapy in metastatic breast cancer

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Background: Many chemotherapeutic options exist for metastatic breast cancer (MBC) but there is no standard regimen. We tested a sequential combination regimen using Cisplatinum and Vinorelbine (PVn) followed by Docetaxel as first-line chemotherapy in a phase II clinical trial. This is the first study using a non-anthracycline sequential combination chemotherapy of PVn with Docetaxelin MBC. Methods: Thirty-five patients were enrolled. Cisplatin 80 mg/m2, which was given on day 1 and Vinorelbine 30 mg/m2 on days 1 and 8 q3 weeks for 4 cycles. After the 4th cycle, responding patients received Docetaxel 75 mg/m2 every 21 days for a maximum of 4 cycles. Patients were evaluated every two cycles and those who had no response were offered other therapy. Patients who showed progression after 2 cycles of PVn were offered Docetaxel but were considered off protocol. Three patients were excluded from analysis because of death unrelated to treatment. Results: After a median follow up of 14 months (range 1–36), 32 patients (91.4%) completed the study. Overall response rate was 53.1%. Complete remission was seen in 5 pts (15.6%), partial response in 12 patients (37.5%), stable disease in 6 patients (18.75%), and progressive disease in 9 patients (28.1%). 20 patients (62.5%) were alive at 12 months. Median time to disease progression was 8 months (range 1–24). At 24 months 37.5% (12 patients) were alive. Response rates to PVn were not significantly improved by sequential addition of Docetaxel. A total of 183 cycles were administered with a median of 6 cycles per patient. Delay of chemotherapy because of Grade II neutropenia occurred in 41/183 cycles (22.4%). Febrile neutropenia was observed in 4 patients (2.2%). Grade II anemia was observed in 40/183 cycles (21.8%) and Grade III in 24/183 cycles (13.1%). Grade II nephrotoxicity occurred in 12 cycles (6.5%) and Grade III vomiting was observed in 31/183 cycles (16.9%). No treatment-related mortality has been reported. Conclusions: Sequential PVn-Docetaxel is a feasible and effective non-anthracycline option as first-line chemotherapy in patients with MBC. More effective Docetaxel may be better used upfront and followed by PVn. This regimen has acceptable toxicity as well.

No significant financial relationships to disclose.

Hepatocellular carcinoma in Lebanon: Etiology and prognostic factors associated with short-term survival

AIM: To study the epidemiology of HCC in Lebanon and prognostic factors predictive of early mortality.

METHODS: An observational follow-up cohort study of HCC cases diagnosed over a five-year period was carried out. Multivariate analysis was conducted to identify prognostic factors in comparison to Cancer of the Liver Italian Program (CLIP) score. Multiple variables including the etiology of underlying liver disease, the demographic characteristics of patients, and the severity of liver disease evaluated by the Child-Pugh score were studied. Tumor parameters included the time of diagnosis of HCC, alpha-fetoprotein level, number and size of nodules, presence of portal vein thrombosis, and treatment modalities. Death or loss of follow-up was considered as an end-point event.

RESULTS: Ninety-two patients (mean 60.5 ± 22.3 years) were included. Etiology of underlying disease was hepatitis B, C, and alcohol in 67%, 20%, and 23.5% respectively. Child-Pugh class at diagnosis was A, B, and C in 34.8%, 39.3% and 25.8% respectively. Overall survival was 44.8%, 32.8% and 17.6% at 1, 2 and 3 years respectively (mean F/U 40.2 ± 23.5 mo). Multivariate analysis identified three predictors of early mortality (< 6 mo): bilirubin > 3.2 mg/dL (P < 0.01), HCC as first presentation of liver disease (P = 0.035), and creatinine > 1 mg/dL (P = 0.017). A score based on these variables outperformed the CLIP score by Cox proportional hazard. ROC curve showed both models to be equivalent and moderately accurate.

CONCLUSION: HBV is the leading cause of HCC in Lebanon. Independent predictors of early mortality are elevated bilirubin, creatinine and HCC as first manifestation of disease. Prospective validation of a score based on these clinical parameters in predicting short-term survival is needed.

The use and abuse of antibiotics in elective colorectal surgery: The Saga Continues…

BACKGROUND

The role of antibiotic prophylaxis in preventing post-operative complications in patients undergoing elective colorectal surgery is well established. Despite evidence that a single-dose prophylaxis is sufficient, the duration of antibiotic use in clinical practice is highly variable and surveys have identified persistent patterns of antibiotic abuse in elective colorectal surgery.

MATERIALS AND METHODS

We conducted a retrospective review of all patients who underwent elective colorectal surgery between 1998 and 2002 at the American University of Beirut Medical Center. A survey among general surgeons in Lebanon was also performed to investigate the pattern of antibiotic prophylaxis used in such cases. The MEDLINE database (1966-2004) was searched for English-language articles and abstracts on antimicrobial use in elective colorectal surgery. Papers cited in relevant primary articles were also reviewed. Data were extracted and reviewed by all authors.

RESULTS

Two hundred and eleven matching patient-records were identified. A triple regimen including metronidazole, ampicillin and an aminoglycoside was the most commonly used preoperative prophylactic method. Patients received post-operative antibiotics for a mean of 6.66+/-2.62 days. The mean duration of post-operative antibiotic prophylaxis used by the interviewed surgeons was 4.31+/-1.08 days.

CONCLUSIONS

Our study confirms that even when strong evidence exists, surgeons fail to adhere to antibiotic prophylaxis guidelines. This pattern is not unique to Lebanon but is shared to a large extent by surgeons around the world. Adherence to published guidelines and improved education of surgeons are essential to the delivery of cost-effective medical practice.

Successful living-related liver transplantation for familial hypercholesterolemia in the Middle East

Familial hypercholesterolemia (FH) is an autosomal dominant inherited metabolic disorder resulting in advanced vascular atherosclerosis and premature death, primarily from coronary artery disease. The primary defect is a mutation in the gene encoding for the plasma LDL receptor located on the short arm of chromosome 19. Liver transplantation is currently the most effective method of treating this disorder. Living-related liver transplantation (LRLT) has become an excellent modality for treating children, including those with inherited metabolic diseases. In this paper, we describe the first report of a LRLT for familial hypercholesterolemia and review FH and the role of liver transplantation.

Inferior vena cava obstruction in Budd-Chiari syndrome: successful treatment by radiological stenting followed by a portosystemic shunt

Surgical decompression by a portosystemic shunt in Budd-Chiari syndrome depends on the caval state. Obstruction of the inferior vena cava (IVC) precludes such an operation due to the risk of reduced blood flow across the shunt and subsequent thrombosis. Similar risks are encountered in more complicated operations such as mesoatrial shunt. We report a patient with Budd-Chiari syndrome in whom obstruction of the intrahepatic IVC by a hypertrophied caudate lobe of the liver precluded the construction of a standard portocaval shunt. A two-step procedure with preoperative radiological stenting of the narrowed IVC followed by a portocaval shunt was successfully performed. This is the fifth case reported in the literature of such an approach.

Common bile duct obstruction secondary to a balloon separated from a Fogarty vascular embolectomy catheter during laparoscopic cholecystectomy

Laparoscopic instrumentation of the common bile duct (CBD) via the transcystic route or through direct choledochotomy seems to be safe, but in rare cases, complications such as pancreatitis, bile duct damage, and hemorrhage from cystic artery may occur. We report an unusual complication with this approach. A 62-year-old man with gallbladder stones presented with obstructive jaundice, mild pancreatitis, and a dilated CBD. He underwent laparoscopic cholecystectomy with an intraoperative cholangiogram through the cystic duct. A small stone seen in the CBD was removed using a 6-Fr vascular Fogarty catheter. Two days later, he became jaundiced again with a rising bilirubin. An endoscopic retrograde cholangiogram showed a 1.5-cm round filling defect floating in a dilated CBD. A sphincterotomy was performed, and a balloon catheter was inflated proximally and pulled down. To our surprise, the filling defect was a crystal clear object, which we finally realized was a fully inflated Fogarty catheter balloon. The balloon spontaneously deflated while being caught with a basket. Surgeons should be aware of this possible complication, and every effort should be made to verify that the balloon still is in place after removal of the embolectomy catheter. Whether vascular embolectomy catheter balloons are appropriate for stone removal or more rigid balloons should be used needs further evaluation.

Laparoscopic colorectal resections. Initial experience at the AUB-MC

BACKGROUND

Laparoscopic colorectal surgery has many advantages to offer. However, it is a complex procedure, and demands advanced technical skills and instrumentation. In addition, its safety when applied to malignant disease is debatable. In this article, we present the early experience and short term results of laparoscopic colorectal resections performed at the American University of Beirut Medical Center.

PATIENTS AND METHODS

Between March 1997 and August 1998, 14 patients with various colorectal lesions underwent attempt at laparoscopic colorectal resection, at the American University of Beirut Medical Center. Seven patients were males (50%) and 7 were females (50%); their mean age was 59 yrs (range 40-73 yrs). Ten patients (72%) had malignant disease and 4 patients (28%) had benign disease.

RESULTS

The operation was completed in 13 out of 14 patients (93%). The overall mean operative time was 176 min (range 135-270 min). The operation was taking less time as surgeons gained experience. The average hospital stay was 7.6 days (range 4-11 days). The last four patients, however, stayed less than six days in the hospital. There were no mortalities. There were three complications (21%), two patients had wound infection, and one patient had a prolonged ileus. All were managed conservatively. Ten patients had malignant disease. In these patients, the operative margins were clear of disease. The average number of lymph nodes retrieved was 10.4 (range 3-19). These patients were followed up for an average period of 7.4 months (range 1-16 months). There was one recurrence. There was no port site metastasis in any patient.

CONCLUSION

Laparoscopic colorectal surgery is feasible and safe. The preliminary results are encouraging. Its application in malignant disease still awaits the results of prospective studies.

Penetrating trauma to the abdominal vessels

Between January 1975 and December 1989, 1860 patients were admitted to the American University of Beirut Medical Centre with abdominal injuries. Their mean age was 23 years. Of these patients 107 had vascular injuries (an incidence of 6%). Bullets were the most common injurious agents (72%), followed by shrapnel (22%). There were 28 arterial and 113 venous injuries. All patients presented to the emergency unit within 5 h of injury (mean 45 min) and were surgically explored. The overall mortality rate was 36.5%. Patients who were haemodynamically stable had a better outcome than those who presented in shock (P < 0.005). The major cause of death was haemorrhage from uncontrolled bleeding. Two subgroups with a higher mortality were identified: patients with inferior vena caval injury associated with a liver injury had a mortality rate of 78.5%, and those with vascular injury associated with pelvic fracture had a mortality rate of 57% (P < 0.05). Abdominal vascular injuries have a high mortality rate, especially if the inferior vena cava is involved or associated pelvic fractures are present. Prompt resuscitation and control of bleeding are the key to an improved salvage rate.

Penetrating missile embolisation

The present case report is that of a 13-year-old boy, who was admitted to the Emergency Unit at the American University of Beirut Medical Center (AUBMC), with a bullet injury to the right upper quadrant with no exist. Chest X-ray and KUB failed to reveal the bullet and there was no evidence of haemo- or pneumothorax. X-ray of both thighs showed the bullet at the level of the right groin. The bullet penetrated the liver, diaphragm and pericardium. It entered through the left ventricle and embolised through the arterial circulation to the right superficial femoral artery. Included in this report is a review and analysis of patients with missile embolisation, who were treated at the AUBMC over the last 10 years.