The ageing process encompasses progressive dysfunction in almost every organ in almost every organism, forming an immense challenge to modern medicine that seems to require many parallel interventions addressing an increasingly complex series of age-related conditions. A set of ‘Hallmarks of ageing’ have been defined, providing a framework for understanding ageing pathologies at the cellular and organismal level, but how these hallmarks arise and how cells respond to them often remains unclear (Lopez-Otin et al. 2013). Given the complexity of the process, it is not too surprising that an array of studies of the ageing transcriptome have been undertaken over the past two decades attempting to shed light on the underlying drivers of pathology. These studies have spanned organisms from yeast to man, taking advantage of the remarkable conservation of ageing pathology across eukaryotes to examine the ageing process in experimentally tractable model organisms. However, major challenges have been encountered in the performance of reproducible experiments and the extraction of meaningful data; early studies, particularly in higher eukaryotes, found few changes in common, and it is only with more recent meta-analyses of giant cross-sectional datasets that a consensus is starting to emerge on a set of gene expression changes that are associated with ageing. Here we survey the literature of transcriptomic changes associated with normal ageing across evolutionarily diverse eukaryotes and describe a set of potential gene expression hallmarks indicative of underlying age-linked gene expression programmes.
A new study provides the most detailed report to date of the cellular effects of a calorie-restricted diet in rats. While the benefits of caloric restriction have long been known, the new results show how this restriction can protect against ageing in cellular pathways.
If you want to reduce levels of inflammation throughout your body, delay the onset of age-related diseases, and live longer--eat less food. That's the conclusion of a new study by scientists that provides the most detailed report to date of the cellular effects of a calorie-restricted diet in rats. While the benefits of caloric restriction have long been known, the new results show how this restriction can protect against ageing in cellular pathways, as detailed in the journal Cell.
"We already knew that calorie restriction increases life span, but now we've shown all the changes that occur at a single-cell level to cause that," says the senior author of the new paper. "This gives us targets that we may eventually be able to act on with drugs to treat ageing in humans."
Stoicism originated as a Hellenistic philosophy, founded in Athens by Zeno of Citium (modern-day Cyprus), c. 300 B.C.E. It was influenced by Socrates and the Cynics, and it engaged in vigorous debates with the Skeptics, the Academics, and the Epicureans. The name comes from the Stoa Poikile, or painted porch, an open market in Athens where the original Stoics used to meet and teach philosophy. Stoicism moved to Rome where it flourished during the period of the Empire, alternatively being persecuted by Emperors who disliked it (for example, Vespasian and Domitian) and openly embraced by Emperors who attempted to live by it (most prominently Marcus Aurelius). It influenced Christianity, as well as a number of major philosophical figures throughout the ages (for example, Thomas More, Descartes, Spinoza), and in the early 21st century saw a revival as a practical philosophy associated with Cognitive Behavioral Therapy and similar approaches. Stoicism is a type of eudaimonic virtue ethics, asserting that the practice of virtue is both necessary and sufficient to achieve happiness (in the eudaimonic sense). However, the Stoics also recognized the existence of “indifference” (to eudaimonia) that could nevertheless be preferred (for example, health, wealth, education) or dispreferred (for example, sickness, poverty, ignorance), because they had (respectively, positive or negative) planning value with respect to the ability to practice virtue. Stoicism was very much a philosophy meant to be applied to everyday living, focused on ethics (understood as the study of how to live one’s life), which was in turn informed by what the Stoics called “physics” (nowadays, a combination of natural science and metaphysics) and what they called “logic” (a combination of modern logic, epistemology, philosophy of language, and cognitive science).
Sources of information on the Stoics
Since the Stoics stress the systematic nature of their philosophy, the ideal way to evaluate the Stoics’ distinctive ethical views would be to study them within the context of a full exposition of their philosophy. Here, however, we meet with the problem about the sources of our knowledge about Stoicism. We do not possess a single complete work by any of the first three heads of the Stoic school: the ‘founder,’ Zeno of Citium in Cyprus (344–262 BCE), Cleanthes (d. 232 BCE) or Chrysippus (d. ca. 206 BCE). Chrysippus was particularly prolific, composing over 165 works, but we have only fragments of his works. The only complete works by Stoic philosophers that we possess are those by writers of Imperial times, Seneca (4 BCE–65 CE), Epictetus (c. 55–135) and Emperor Marcus Aurelius (121–180) and these works are principally focused on ethics. They tend to belong on moral exhortation but give only clues to the theoretical bases of the moral system. For detailed information about the Old Stoa (i.e. the first three heads of the school and their pupils and associates), we have to depend on either doxographies, like pseudo-Plutarch Philosophers’ Opinions on Nature, Diogenes Laertius’ Lives of Eminent Philosophers (3rd c. CE), and Stobaeus’ Excerpts (5th c. CE) – and their sources Aetius (ca. 1st c. CE) and Arius Didymus (1st c. BCE–CE) – or other philosophers (or Christian apologists) who discuss the Stoics for their own purposes. Nearly all of the latter group are hostile witnesses. Among them are the Aristotelian commentator Alexander of Aphrodisias (late 2nd c. CE) who criticises the Stoics in On Mixture and On Fate, among other works; the Platonist Plutarch of Chaeronea (1st-2nd c. CE) who authored works such as On Stoic Self-Contradictions and Against the Stoics on Common Conceptions; the medical writer Galen (2nd c. CE), whose outlook is roughly Platonist; the Pyrrhonian sceptic, Sextus Empiricus (2nd c. CE); Plotinus (3rd c. CE); the Christian bishops Eusebius (3rd–4th c. CE) and Nemesius (ca. 400 CE); and the sixth-century Neoplatonist commentator on Aristotle, Simplicius. Another important source is Cicero (1st c. BCE). Though his own philosophical position derives from that of his teacher Philo of Larissa and the New Academy, he is not without sympathy for what he sees as the high moral tone of Stoicism. In works like his Academic Books, On the Nature of the Gods, and On Ends he provides summaries in Latin, with critical discussion, of the views of the major Hellenistic schools of thought.
From these sources, scholars have attempted to piece together a picture of the content, and in some cases, the development of Stoic doctrine. In some areas, there is a fair bit of consensus about what the Stoics thought and we can even attach names to some particular innovations. However, in other areas, the proper interpretation of our meagre evidence is hotly contested. Until recently, non-specialists have been largely excluded from the debate because many important sources were not translated into modern languages. Fragments of Stoic works and testimonial in their original Greek and Latin were collected into a three-volume set in 1903–5 by H. von Arnim, Stoicorum Veterum Fragmenta. In writings on the ‘old’ Stoics, fragments and testimonia are often referred to by von Arnim’s volume numbers and text numeration; e.g. SVF I.345=Diogenes Laertius, Lives 4.40. In 1987, A. A. Long and David Sedley brought out The Hellenistic Philosophers (LS) which contains in its first volume English translations and commentary of many important texts on Stoics, Epicureans and Skeptics. In 1988 Long and Sedley was followed by a collection of primary texts edited by B. Inwood and L. P. Gerson entitled Hellenistic Philosophy. Unless otherwise specifically noted, I refer in what follows to texts by or about Stoics using the author’s name followed by Long and Sedley’s notation for the text. For example, ‘Aetius, 26A’ refers to section 26 of Aetius’s work, text A (unless otherwise noted, I use their translation, sometimes slightly altered). The Inwood and Gerson collection translates many of the same texts, but unlike LS does not chop them up into smaller bits classified by topic. Each approach has its merits, but the LS collection better serves the needs of an encyclopedia entry. For French translation of Chrysippus, see Dufour (2004). For a German translation of the early Stoa, see Nickel (2009).
Thanks, https://plato.stanford.edu/
https://www.iep.utm.edu/
