Jean Camus and Gustave Roussy: pioneering French researchers on the endocrine functions of the hypothalamus

Identification of a potentially functional circRNA-miRNA-mRNA regulatory network in type 2 diabetes mellitus by integrated microarray analysis

BACKGROUND

Circular RNAs (circRNAs) function as miRNA sponges by adsorbing microRNAs (miRNAs), thereby regulating messenger RNA (mRNA) expression. The circRNA-miRNA-mRNA regulatory network associated with type 2 diabetes mellitus (T2DM) has rarely been explored. A circRNA-miRNA-mRNA regulatory network associated with T2DM was established to help deepen our understanding of the molecular mechanism of and therapeutic targets for T2DM.

METHODS

Differentially expressed circRNAs (DEcircRNAs), miRNAs (DEmiRNAs), and mRNAs (DEmRNAs) were derived from the Gene Expression Omnibus (GEO) microarray datasets GSE114248, GSE51674 and GSE95849, respectively. A circRNA-miRNA-mRNA regulatory network associated with T2DM and its subnetwork were constructed. The hub genes were screened using a protein-protein interaction (PPI) network. Finally, a hub gene-related network was constructed. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed.

RESULTS

The circRNA-miRNA-mRNA network included 9 circRNAs, 24 miRNAs and 320 mRNAs. When four key circRNAs (circMYO9B, circGRAMD1B, circTHAP4 and circTMC7) were chosen, the subnetwork contained 4 circRNAs, 18 miRNAs and 307 mRNAs. Afterwards, 8 hub genes (SIRT1, GNG7, KDR, FOS, SIN3B, STAT1, SP1, and MAPK3) were extracted from the PPI network. GO and KEGG pathway analyses revealed that the network might be involved in oxidative stress responses, regulation of inflammation, neovascularization, endocrine and cancer-related processes, etc.

CONCLUSIONS

A circRNA-miRNA-hub gene regulatory network was constructed, and the potential functions of the hub genes were analyzed. Four important circRNAs (circMYO9B, circGRAMD1B, circTHAP4 and circTMC7) might be involved in the occurrence and development of T2DM, and this finding provides new insight into the molecular mechanism of and therapeutic targets for T2DM and its complications. Future studies are needed to validate the sponge effects and mechanisms of these 4 circRNAs.

The Pioneer Neuropharmacologist Alfred Fröhlich (1871-1953) and the Origins of Neuroendocrinology: A Sesquicentennial Remembrance

The birth of neuroendocrinology as a scientific discipline is traced back to 1900-1901, when Joseph Babinski, Alfred Fröhlich, and Harvey Cushing independently identified adiposogenital dystrophy (Fröhlich syndrome), and related gonadal underdevelopment and obesity to a tumor near the pituitary gland. This discovery prompted decades of research into the brain mechanisms responsible for the control of peripheral metabolism and endocrine functions. On the occasion of the 150th anniversary of Fröhlich's birth, this study traces the origins of his intellectual formation and his association with renowned contemporaries in Austria, England, Italy, and finally Cincinnati, Ohio, where he sought refuge after Austria's annexation by Nazi Germany. Fröhlich interacted with seminal figures in biomedicine, including Lothar von Frankl-Hochwart, Hans Horst Meyer, Ernst Peter Pick, Harvey Cushing, John Newport Langley, and the Nobel laureates Charles Scott Sherrington and Otto Loewi. Alfred Fröhlich, one of the 20th century's most emblematic physicians, left his mark on neurophysiology and neuropharmacology with important works, and published authoritative manuals of drug dispensing and clinical therapy. He confronted the calamities of two World Wars with remarkable resilience like many of his Viennese colleagues who, overcoming the constraints of National Socialism, settled overseas to fulfil their calling as physicians, researchers, and teachers.

Percival S. Bailey: eminent scholar of neurosciences who revealed the workings of the hypothalamus through clinicopathological research on craniopharyngiomas

Percival S. Bailey (1892-1973) was a scholar, neuroscientist, neuropathologist, and neurosurgeon who made decisive contributions in the field of neuro-oncology. Far less known are his groundbreaking insights into understanding hypothalamic physiology through the study of craniopharyngiomas. As one of Harvey W. Cushing's most talented trainees, Bailey was instrumental in developing Cushing's project of a histologically based prognostic classification of brain tumors. He worked at Peter Bent Brigham Hospital on and off between 1919 and 1928, owing to frequent clashes with his mentor. A major cause of this long-term conflict was Bailey's 1921 experimental demonstration of the hypothalamic origin of diabetes insipidus and Fröhlich's syndrome. This finding challenged Cushing's view that both alterations were due to pituitary gland insufficiency. In a seminal monograph written with John F. Fulton in 1929, both authors provided the first comprehensive account of the specific hypothalamic disturbances caused by tumors that originated within the infundibulum and third ventricle. The methodical study of Cushing's craniopharyngioma specimens allowed Bailey to recognize the close contact between these lesions and hypothalamic nuclei, a key concept that Bailey originally advanced for proper surgical planning. This article aims to credit Bailey for his pioneering definition of craniopharyngiomas as tumors with a true intrahypothalamic position.

Cystic tumors of the pituitary infundibulum: seminal autopsy specimens (1899 to 1904) that allowed clinical-pathological craniopharyngioma characterization

A heterogeneous group of epithelial cystic tumors developed at the infundibulum and the third ventricle disconcerted pathologists at the dawn of the twentieth century. Very little was known at that time about the physiological role played by the pituitary gland, and there was almost complete ignorance regarding the function of the hypothalamus. Acromegaly, or enlargement of acral body parts, described in 1886 by Pierre Marie, was the only disease linked to primary hypertrophies of the pituitary gland, known as "pituitary strumas". A growing number of young patients manifesting an unexplained combination of physical and mental symptoms, including absent or delayed sexual maturation, progressive obesity, abnormal somnolence, and dementia-like changes in behavior were reported to present large solid-cystic tumors which characteristically expanded within the infundibulum and third ventricle, above an anatomically intact pituitary gland. Between 1899 and 1904, five seminal autopsy studies from different countries thoroughly described the anatomical relationships and histological features of this newly recognized type of infundibular tumors. These cases were instrumental in fostering the systematic investigation of similar lesions by the Austrian pathologist Jakob Erdheim (1874-1937), who in 1904 was able to classify these infundibulo-tuberal cysts under the common category of hypophyseal duct tumors. The pioneering American neurosurgeon Harvey Cushing (1869-1939) unsuccessfully attempted to surgically remove one of these cysts, for the first time in history, in 1902. The term "craniopharyngioma", chosen by Cushing in 1929 to designate these lesions, would eventually prevail over Erdheim's more accurate denomination, which linked their origin to squamous cell remnants derived from the embryological structures that give rise to the pituitary gland. This paper presents a comprehensive, renewed account of the five clinical-pathological reports which laid the groundwork for the proper clinical diagnosis, topographic conceptualization and pathological categorization of craniopharyngiomas.