<PERSON> (c.380-315 BC) wrote a history of the reign of <PERSON>, including a digression concerning the fabulous island of Meropis. We don't have the full text of this work, but the Meropis fragment is preserved in the Varia Historia by Aelian, book 3, chapter 18.
On its far border is the land of Anostos ("no-return") which has two rivers, Pleasure and Grief, with fruit trees growing along each. Eating from the Grief trees will cause you to have a miserable life and then die. The Pleasure fruits result in you aging backwards.
The other Trees which grow by the River of Pleasure produce fruit of a contrary nature, for who tasts thereof shall be eased from all his former desires : If he loved any thing, he shall quite forget it ; and in a short time shall become younger, and live over again his former years : he shall cast off old age, and return to the prime of his strength, becoming first a young man, then a child, lastly, an infant, and so die.
(English translation by <PERSON>, 1665)
ὃς γὰρ ἂν γεύσηται τούτων, τῶν μὲν ἄλλων τῶν πρότερον ἐπιθυμιῶν παύεται, ἀλλὰ καὶ εἴ του ἤρα καὶ αὐτοῦ λαμβάνει λήθην, καὶ γίνεται κατὰ βραχὺ νεώτερος καὶ τὰς φθανούσας ἡλικίας καὶ τὰς ἤδη διελθούσας ἀναλαμβάνει ὀπίσω. τὸ μὲν γὰρ γῆρας ἀπορρίψας ἐπὶ τὴν ἀκμὴν ὑποστρέφει, εἶτα ἐπὶ τὴν τῶν μειρακίων ἡλικίαν ἀναχωρεῖ, εἶτα παῖς γίνεται, εἶτα βρέφος, καὶ ἐπὶ τούτοις ἐξαναλώθη.
(Greek text from <PERSON> edition, 1866)
The <PERSON> account is sometimes thought to be a parody of classical political utopia stories, specifically including <PERSON>'s version of the Atlantis legend. 351
<PERSON> was a pupil of <PERSON>, <PERSON>'s rival in Athens. It's possible that the aging-backwards bit is specifically riffing on <PERSON>'s Statesman (Πολιτικός), which includes some cosmological ideas about occasional reverses in the flow of time.
In that dialogue, <PERSON> is joined by a kinsman, "young <PERSON>", and a <PERSON> (ξένος, presumed to be the same character as in The Sophist). The <PERSON> explains that they have heard about two stories, the long-ago "age of <PERSON>" when people were born spontaneously out of the earth; and that the present east-to-west motion of the sun is attributable to the kingship of <PERSON>. (From other sources, he'd requested <PERSON> to change the heavens from their former opposite arrangement in order to prove divine sanction for his claim.)
He says that these are part of a larger history, where God will occasionally stop pushing time forwards, and that it will then flow backwards for a while before God nudges it on again. The moments of reversal are catastrophic. 351